It is still dark as Washington awakens from the three-day Fourth of July weekend: 5:15 a.m. on Monday, July 7, 1997. The day-shift supervisor arrives to begin the new week at the Starbucks on Wisconsin Avenue in Georgetown. In the parking lot, she sees the Saturn coupe belonging to the night-shift supervisor, Caity Mahoney. This is odd; Caity should have closed up at 8 the night before. The day supervisor unlocks the door, steps inside. The lights are on. Music is playing. A rag and cleaning fluid are out. A broom and dustpan slant against a booth. On the counter is a work schedule and a muffin, unwrapped. Farther on, in a back room and hallway, she finds them. Mary Caitrin Mahoney, 16 days short of her 25th birthday. Emory Allen Evans, 25. Aaron David Goodrich, 18. She runs out into the street and flags down a bus. The driver calls 911.

The three killings that came to be known as the Starbucks case were perhaps the D.C. murders of the late 1990s, generating an enormous wave of fear and talk and a $100,000 reward, then a record for the District. They gripped the city with a force that is hard to conjure up today, in this post-sniper, post-9/11 world, where a feeling of constant vulnerability is ingrained. Back then, it was possible to be utterly shocked by a local crime, to be penetrated in the tender areas of one's pysche.

In a city that contended year after year for the title of murder capital of the United States, Starbucks crossed several lines. In the 1990s, 300 or 400 people died each year at the hands of others in the District. Yet all but a handful died "east of the Park" -- Rock Creek Park, the unofficial dividing line between white and black Washington. Starbucks was "west of the Park." And it was in Georgetown, a sanctuary within a sanctuary, a citadel of upper-crust Washington that had seen only eight murders in the previous eight years. On top of that, violent, bloody death had crept not into a bar or an alley or a parking lot, but into a snug Starbucks.

The Starbucks case intersected with a nadir in the history of the D.C. police department's homicide investigations. That summer the homicide unit's case-closure rate stood at an all-time low -- 34 percent -- and Chief Larry D. Soulsby had responded by transferring more than 70 homicide detectives out to the district substations, leaving a smaller number of veterans at headquarters to handle high-profile cases.

Intense pressure mounted to solve the case. Images of the victims dominated the airwaves: Caity, the diligent night manager, an honors graduate of Towson State, a former White House intern. Emory, only three weeks on the job, an only child who had moved to the District from New Jersey, saving money to attend Howard University, where he wanted to major in music. Aaron, the baby at 18, not originally scheduled to work that night, who had picked Starbucks over a job as a security guard.

For police, the Starbucks case was first and foremost a mystery. Caity lay in the hall, shot five times, once in the chest and four times in the head at close range. The store key ring, with the safe key, lay beneath her right leg. Emory and Aaron, shot three times and once, respectively, lay in the back room near the safe, which was unopened and still contained $10,000 from the busy weekend traffic. The killer or killers had taken three lives and left with nothing. They also left no witnesses, no fingerprints and no physical evidence except the shell casings on the floor and the slugs, as good as useless with no gun to match them.

The slugs came from two guns, a .380 semiautomatic pistol and a .38 revolver, suggesting two killers. Evidence technicians found a slug in the back room's ceiling: a warning shot. Could it have been a robbery gone bad? The killer had singled Caity out with a special viciousness. Could it have been personal?

Detectives immediately began interviewing store employees and delving into the victims' backgrounds. Caity had no ex- or current boyfriend. They did find an ex-employee Caity had recently caught stealing from the safe. But he was ruled out. In the first few months, numerous false leads arose, 23 separate suspects, each laboriously considered and eventually discarded.

After two months, the city's highest-profile murder case was going nowhere.

The essential difference between homicide investigation on TV and homicide investigation in real life is one of degree: The true art of homicide investigation is both subtler and sloppier, much more mundane and, finally, much more sublime -- a grinding application of routine, the occasional piece of luck, a marathon of wits and will. If genius is an infinite capacity for taking pains, then real-life homicide investigation can have a genius of its own.

The Detectives

At 42, Det. Jim Trainum had built a reputation as one of the best investigators in the department. In contrast to some in D.C.'s central homicide unit, he was not noted as a sharp dresser or a man with street flash. He had been a paramedic before he became a cop, and he had only a high school education, but he also had a sharp, questioning mind. He was known for his meticulous, thinking-man's approach. And he had once been written up in Forbes magazine after he busted one of the biggest fencing operations in the city; a white guy, he had gone undercover in the inner city and fooled everyone into thinking he was a junkie.

"Street thugs think cops are macho types, and Jim's not that way," says Jim Vucci, who was Trainum's sergeant for 10 years. "And it threw them off. They're not threatened by him. If they only knew what comes out of the end of his pen. Jim was the very best detective I ever worked with."

Trainum was on Starbucks from Day One, along with Det. Tony Patterson, who was assigned to the case as part of the regular rotation. Trainum immediately turned to a man many considered the smartest homicide investigator around, an FBI agent based in the District named Brad Garrett.

Garrett, 48, could not have appeared more different from Trainum. Where Trainum was garrulous, messy and plumpish, Garrett was streamlined, taciturn and taut. An ex-Marine and ex-federal parole officer, he still looked like the fashion model he had once been, but for a scary, laserlike intensity tempered only slightly by a Zen quality. In matters of dress he went in for clothes by Hugo Boss and Armani, often entirely in black. He had a PhD in criminology from the University of Louisville, and he was just coming off one of the greatest investigative triumphs in the recent history of the FBI, a 4 1/2-year manhunt that snared Mir Aimal Kasi, a Pakistani who had killed two CIA employees in 1993 outside the agency's headquarters in McLean. On a previous trip to Pakistan, Garrett had helped catch Ramzi Yousef, the mastermind of the first attack on the World Trade Center. With both Kasi and Yousef, Garrett had elicited confessions on the plane rides back from Pakistan.

Garrett was something of a local legend within area law enforcement -- his nickname was "Dr. Death," a nod to his prowess as well as to his doctorate, his black wardrobe and his undertaker's calm. That reputation had led Trainum to seek out Garrett to consult on a case in 1994. In talking that case over, each found he liked the way the other's mind worked. Trainum was the energetic tactician, always grasping for a solution. Garrett was the cool strategist, always seeking patterns. "The reason he and I work so well together is we're willing to not get locked into one thought. To look at it as a puzzle," Garrett says. "The way you solve a puzzle is you just keep adjusting what you are doing."

They continued to consult each other, informally, on their cases. This was more than unusual. FBI agents often disdain locals as less skilled, and cops often resent the feds for their greater resources. But here a rare friendship took flight. For all their surface differences, they were kindred souls, soft-spoken, mild-mannered, cerebral. They didn't threaten and they didn't pound desks. They were considerate and respectful, to perpetrators as well as to victims' families.

Trainum invited Garrett to join him on Starbucks. The unique jurisdiction of Washington -- as the "federal city," it allows FBI agents to work on local crimes -- smoothed Garrett's entry into the case. The two started with a visit to the crime scene. The store was shuttered, blood still on the tile floor. They considered the positions of the bodies, the trajectories of the bullets, the bloodstains, the close quarters. They measured and paced and lay on the floor. They quickly concluded robbery-gone-bad: the warning shot, the two guns, the money in the safe, all of it pointed that way. Most likely two men. The robbers had herded the three employees into the back room. Caity, conscientious and forceful, had perhaps tried to talk, so the robbers fired off a shot to regain control. But the shot made a huge echoing sound in the enclosed space, and in that hair-trigger moment they lost control instead, the detectives guessed. Caity reacted, fleeing into the hallway, where the robbers gunned her down before turning to shoot the other two.

When murder is paired with another crime -- rape-murder, drug-murder, robbery-murder -- detectives look first at the other crime. Trainum and Garrett were looking for robbers who "went hard" -- street slang for gunplay -- and started shooting when they lost control. A commercial robbery of this magnitude took planning and guts. It took experience.

The Tip

At 11 p.m. on September 28, a Sunday, almost three months after the killings, an anonymous caller phoned D.C. Homicide. The caller, who was given the ID number 234, told a detective that he knew who had done Starbucks. Two guys, one named "Carl." The caller didn't have a last name for Carl, but he had a description: short, brown skin, mid-twenties, 130 to 147 pounds, with a beard and possibly a mustache. Carl lived with his wife, mother and kids on Gallatin Street NE. Carl drove a small economy car, and normally carried two or three guns. The caller said Carl's accomplice shot the black guy -- Emory Evans -- after he "bucked," or resisted. Carl then shot the other two. "The caller added that he knows this information is better than anything else we have," the detective wrote.

A few days later, 234 called back. He added that Carl was "pretty vicious. He's got more than one body" -- he had killed prior to Starbucks. Carl "always uses a partner when he's doing a robbery. He killed his last partner because he gave up his name." 234 promised to call back.

Immediately after the first call, Trainum went to work. In the Department of Motor Vehicles database he found only one Carl in the correct age range on Gallatin Street: Cooper, Carl Derick, aka Cooper, Carl Derek Havord. He was 28 and slight, 5-feet-8, 133 pounds. His wife had a 1994 Honda Civic.

Trainum ran Cooper's name through two criminal history databases, federal and local, and found he had a long police record: seven arrests, including a 1990 armed robbery conviction that brought a two-year sentence. Trainum got the files. They matched 234's tip almost perfectly.

Cooper and a friend, Montee Goodman, had stuck up a couple of 7-Elevens in Maryland in 1989. At the second, a witness saw their car and tag. Police spotted the car a few days later and caught Goodman, who confessed, implicating Cooper as the gunman and instigator. Four years later Montee Goodman ended up in a parking lot in Prince George's County with two bullets in the back of his head. The murder was unsolved. Now Trainum went through the Prince George's homicide file and saw the name of the main suspect: Carl Cooper.

Trainum and Garrett were excited, but they told themselves not to get too excited. Cooper could well be an innocent man. Caller 234 could well be wrong. They had no evidence, not the barest circumstantial thread.

Some on the case wanted to scoop up Cooper and sweat him. Public interest had not died down, and there was pressure for a quick arrest. Trainum and Garrett argued for patience. They had to keep working and keep the element of surprise. Their view carried, and they broke off to work Cooper while Patterson pursued other leads.

Trainum and Garrett began to build a detailed profile of Cooper. The more they learned, the more he fit. His father was a church deacon, his mother a biochemist at the National Institutes of Health. Carl had been adopted. His father had died at 72, when Carl was 17. Carl had lived his entire life at the house on Gallatin Street except for the time he had spent in prison and in a facility for troubled youth.

He had long exhibited a volatile temper and attention-deficit problems, dropping out of public school after repeated fights. As he moved through special schools and into the criminal justice system, evaluators found him immature and impulsive, average in intelligence but with excellent abstract-reasoning ability. "The defendant functions on the level void of logic and standards and does what feels good to him," one therapist wrote. Cooper's criminal record started with a small-time drug arrest, followed by car theft, followed by robbery. But he had not been in serious trouble in seven years. He currently worked in security for Wang Government Services Inc. in McLean. His wife was a clerk at Best Buy in Laurel. They had a 2-year-old son.

The detectives understood they were dealing with a canny quarry. Cooper knew all about police and courts. He had withstood the heat before as the main suspect in Montee Goodman's homicide. If he was their man and had continued in his robbery career without getting caught for seven years, he had become quite good, careful and quiet. They would have to be just as careful in laying a trap to snare him.

First, they had to find out who he talked to and who he might have told about Starbucks. They got a court order to monitor his phone, employing devices that recorded the number of every call into or out of the Cooper residence. Rarely used in murder cases, such devices were usually confined to high-level drug trafficking or racketeering probes. They weren't wiretaps -- they recorded only numbers, not talk -- but they were much easier to get than a wiretap. Trainum spent hundreds of hours entering every bit of information generated by the investigation -- all the numbers from the monitoring devices, all the names of suspects and witnesses, all the details of Cooper's background and criminal history -- into a regional police intelligence database.

For their first foray into Cooper's world, Trainum and Garrett visited Montee Goodman's mother and his brother-in-law. When Cooper's name came up, both expressed distaste, but would not elaborate. The brother-in-law, though, did give the detectives the first name of a good friend of Cooper's, a barber. He didn't know the last name. Eight days later, Caller 234 gave them another lead on the man he said was Cooper's accomplice: He worked in a barbershop on Bladensburg Road in Maryland.

Now technology took over. The FBI analyzed Cooper's phone calls and found a frequently called number listed to a woman in Hyattsville. Garrett put the first name they had for the Barber together with the Hyattsville woman's last name and ran the combination through criminal history databases. He got a hit: a 26-year-old man, 6 feet tall, 200 pounds, with a robbery past. Surveillance revealed that he worked at a barbershop.

They had their second suspect.

On October 24, Trainum drove by the Barber's home at 10 minutes after midnight and spotted Cooper's car. That day, Garrett got the okay to monitor the Barber's calls. Five days later, the first bunch of numbers came in.

Now Trainum's effort paid off. The database told them that one of the numbers Cooper and the Barber both called belonged to a 28-year-old woman whose name appeared in the Montee Goodman case. She had been Goodman's girlfriend.

Finally, they had someone who could tie everything together. A possible informant.

The Addict and the Birthday Girl

One of the leads Tony Patterson had been working on was Eric Butera, a recently cleaned-up drug addict who said he had heard people with guns talking about the Starbucks killings in a crack house. Police officers sent Butera back to the rowhouse to make a drug buy that would allow them to search the place. But when Butera showed up at the house on December 4, 1997, he was turned away. He didn't get far before he was jumped by three men, robbed of $80 in marked money and stomped to death. The detectives were parked too far away to see what was happening. Patrol officers responding to a 911 call found the body on the sidewalk 40 minutes later.

The debacle reinforced a growing perception that the Starbucks investigators were Keystone Kops. Two months earlier, Chief Soulsby had transferred the 18 top officials out of Homicide because he was angry about mishandled evidence: The fired Starbucks employee's shoes were not taken in for testing, even though technicians initially thought they had blood on them. The shoes were recovered a day later and found to contain no blood, but the damage to the department's credibility had been done.

Meanwhile, Trainum and Garrett were pursuing Cooper. In February 1998, seven months after the murders, they brought a cake to a house in Southeast to celebrate the 29th birthday of Goodman's ex-girlfriend, whom they had softened up in a visit a week earlier.

The Birthday Girl told Trainum and Garrett she had always suspected Cooper in Goodman's murder. She said Cooper had been angry with Goodman over a drug debt. Cooper and the Barber had done robberies together, she said, giving a few details, but not enough to make an arrest. The detectives asked her about Starbucks, and she recalled that Cooper and the Barber had been involved in something hot around that time. And she added that they had their women buy their guns for them.

Her information seemed good. Trainum spent a day searching by hand through paper records at the Atlantic Guns store in Silver Spring (gun purchase records exist in no electronic database in the United States). It turned out that the year before Starbucks, Melissa Lee Musgrove had purchased a 9mm handgun using a Maryland driver's license with an address in College Park. Musgrove was the maiden name of Cooper's wife, Missy.

A 9mm was the wrong caliber for Starbucks or Montee Goodman. Had it been used in another crime?

The Nephew and the Surgeon's Daughter

One by one, more leads on Cooper turned up. In June 1998, "America's Most Wanted," the TV show that had been responsible for the arrest of more than 500 fugitives, reran a segment on Starbucks that it had done the year before. A 29-year-old woman called the show to say she knew someone who knew the killer. The man she identified had grown up near Cooper. The detectives put a wire on the woman and sent her in to buy drugs from the man's nephew.

To get the nephew to talk about Cooper and Starbucks, the woman on her own launched into a story about a plan to rob some Jamaican drug dealers. The startled detectives heard the woman say she needed somebody to "go hard," somebody the nephew knew: "This person done did a couple of robberies. He got some bodies."

"Carl?" the nephew said.

"What -- what did he do recently that -- that was real big?" the woman asked.

"Starbucks," the man said. The woman said she was uncertain about Carl because he'd left the money in Starbucks. "That's only because the lady ain't give up the -- he told me the whole thing," the man said. "Lady ain't give up the safe."

As the conversation went on, the man appeared to grow suspicious. He had provided independent corroboration of most of Caller 234's account, but turning him into a witness against Cooper wouldn't be easy.

Then the detectives got a lucky break from an unexpected direction. In August 1998, Prince George's County Homicide Det. Sgt. Joe McCann called about Carl Cooper. He was the suspect in a two-year-old robbery of an off-duty Prince George's police officer who was in a car with a woman in a county park. The officer struggled with the robber, who shot him and fled.

A woman in prison in Pennsylvania had told a Prince George's detective in the spring of 1997 that Cooper did the shooting. But the case languished for months after the detective was transferred. Again Trainum's hours of data entry paid off: When Prince George's police officers finally got back to the case and entered Cooper's name into the shared police intelligence database, they hit the link Trainum had inserted connecting Cooper to Starbucks.

From prison, the woman spoke to Garrett about a host of crimes involving Cooper, the Barber and a former boyfriend of hers who went by the street name Man. The woman, a rebellious 28-year-old surgeon's daughter from rural Pennsylvania, had fallen in love with Man. He had taken her to D.C. and introduced her to his best friend, Carl Cooper. And Cooper had let her into the robbery gang he ran. She became their getaway driver, Bonnie to a band of Clydes.

She estimated that in 1995 and 1996 the gang stole 50 cars and did 15 robberies, including one at a Chevy Chase bank, where they got away with $11,000. Man and the Surgeon's Daughter ultimately moved on to Pennsylvania, where they were caught after armed robberies in eight counties. Now the woman was talking in the hope of reducing her prison sentence.

She described Cooper as a master criminal, smart and charming. Although he was the smallest man in the gang, he was the unquestioned leader, feared by all. Key to his success was a willingness to "go hard" -- the others knew that he had bodies in his past -- tempered by a very cautious robbery technique. He staked out his targets to learn routines and to avoid video surveillance. He handed out latex gloves to his crew so no one left prints. He carried two guns.

One night in August 1996 Cooper had called the Surgeon's Daughter after a crime she was not involved in, a robbery gone wrong in Prince George's County. He said he had come upon a couple in a parked car. At gunpoint, he got $20 from the woman, but the man resisted and Cooper decided to kill him, firing twice. As the man begged for his life, the woman screamed his name: "Bruce." When Cooper fired his second shot, he had said, "Goodbye, Bruce." The next day, the Surgeon's Daughter was with Cooper when he learned from television that he had shot a cop named Bruce Howard. "He better die," Cooper said. The officer survived, but he didn't turn out to be much of a threat to Cooper: The composite drawing his recollection produced looked nothing like Cooper.

At the scene, police had recovered two shell casings and a slug from a 9mm pistol. The Surgeon's Daughter said the gun had been purchased by Cooper's wife, Missy. Could the 9mm handgun that shot the officer be the same gun that Missy bought in 1996? Garrett and Trainum had to get the gun.

The Tickle

The Surgeon's Daughter had elevated the Starbucks case into a new class of crime. Suddenly it was not just a single robbery gone wrong. The Surgeon's Daughter had given Trainum and Garrett crisp information, specifics about a robbery gang that could serve as the blueprint for a prosecution under the federal Racketeer Influenced and Corrupt Organizations Act, the key legal weapon against organized criminal gangs. Even if they never solved Starbucks, a RICO conviction would allow the detectives to put Cooper and the Barber away for life.

They had enough to arrest Cooper now. But it was not yet a strong case. They wanted the gun.

The Surgeon's Daughter also enabled them to apply for the most powerful investigative tool in the law enforcement arsenal, one seldom used in a homicide case: a wiretap. To be worthy of a wiretap, the case had to include certain offenses -- racketeering was one of them -- and Garrett had to swear that normal investigative techniques had failed or were too risky. By late August 1998, the detectives had the wiretap.

Cooper would be too careful to talk indiscreetly on the phone, so they came up with a strategy to "tickle" the wire -- a series of steps to get some chatter going. This was naked psychological warfare. They would go at those around Cooper and see how he jumped. They would act, watch him react and adjust accordingly. The goal, they later said, was to "tweak him" and "spin him up," to get him angry and upset enough to make a mistake.

They decided to visit the address Missy had given the gun store when she bought her 9mm -- her mother's house. They assumed that Missy's mother would call her at work, and that Missy would then call Carl. On a Friday afternoon, Trainum and Garrett knocked several times on the doors in College Park. Finally, Missy's mother came to the back door.

She said she no longer had any contact with her daughter. They'd had a falling- out over her marriage to Carl Cooper. She didn't have her daughter's address or phone number.

The detectives played a carefully worked-out ruse: They said they had recovered a gun with all but three of the serial numbers scratched off. They were interviewing people whose guns had a similar series of numbers, trying to find the number on their gun by a process of elimination.

The tickle worked spectacularly. As Trainum and Garrett walked to their car, the pager in Trainum's pocket -- which was recording all messages sent to Cooper's pager -- went off: Missy calling Carl from work. After her number, she had

entered several 911s to indicate extreme emergency.

Trainum smiled.

Later, the detectives listened to the wiretap tapes. They heard Missy talking to the Barber's girlfriend. They couldn't speak freely because Carl was around, so they played a guessing game. "Something Carl did?" the Barber's girlfriend said.

"Maybe," said Missy.

"Slept with somebody?"

"Uh-uh."

"Dealing drugs?"

"No."

"Stole something?"

"No."

Was it car theft? The Barber's girlfriend asked.

"No, uh-uh."

"They robbed some store?"

Missy paused.

"And somebody saw them?"

"Trying to say," Missy said, and paused again. "Oh, somebody trying to say that it happened," the Barber's girlfriend ventured.

"Mm-hmm."

The girlfriend began guessing about robberies Carl and the Barber had committed. "The bank thing?" "No." "The park?" "No."

Missy interrupted the conversation to tell her son to drink his milk. After listening to more errant guessing, she answered with a word: "Georgetown." "Georgetown," the Barber's girlfriend said. She finally got it. "Oh, Starbucks." But Missy said she was sure their men were innocent. "I know in my heart that Carl and them ain't had nothing to do with that," Missy said. "Because they -- they would have got the money."

So Carl knew the detectives were on to him. If he was worried, he didn't let it show. "They all be shooting around in the dark," they heard him tell a friend.

The Gun

Two days later, Carl called Homicide, asking for Trainum. He was out, so Cooper spoke to Tony Patterson. Cooper said Missy's gun was in storage outside the District. He offered to make it available for inspection. He complained about the detectives' visit to his in-laws'.

Trainum and Garrett deliberately let a day pass before they went to the Coopers' house, knowing from surveillance that Missy was home and Carl was at work. But no one answered the door. Trainum used Garrett's cell phone to leave a message.

They let another day pass. Then they went to see Missy on the job at Best Buy. Trainum told her this was a mundane matter that could have been handled by phone, but now, he said, he was suspicious. He knew that Carl was a convicted felon, and he suspected that Carl might be domineering and abusive. Missy said she had tried everything -- marriage, home, children -- to keep Carl straight. Then she made an offer they didn't expect: She said they could pick up the gun at her grandfather's apartment in Maryland after she got off work.

This time Cooper called the lieutenant supervising the whole Starbucks investigation, to express his fury that the detectives had brought up his criminal past with Missy. "Your officers slandered me in the presence of my wife," Cooper said. But he offered cooperation: "In fact, we'll let you even keep the weapon and do -- if you want to do a ballistics or whatever."

Trainum and Garrett began to wonder why Cooper was giving up the gun so easily. Was it a trap? They decided to bring along an FBI agent to wait outside the apartment building as backup. Garrett would wear a wire so the agent could hear them. They didn't know if Carl would be there or not, but they figured the presence of family would add a certain safety factor. Garrett would be good cop, Trainum bad.

That night, outside the grandfather's apartment in Hyattsville, they parked in the lot and immediately saw Carl coming down the stairwell to intercept them. He came on even-tempered and cop-savvy, adopting a stilted tone of officialese. Right off, he let them know he had complained to Trainum's boss: "I had expressed my disappointment in the way that you had went up to my wife's job." Trainum talked while Garrett stayed silent. "If you want to file a complaint with that, you can do so, okay?" Trainum said. "My business is with your wife. I need to ask her questions. Not you." Trainum turned his back on Cooper. Garrett lingered a step behind to watch.

Inside the apartment, Missy sat at one end of a rectangular dining room table, and the gun, an Astra A-100 9mm, rested in a box in plain view at the other end. In between sat several family members, as if they were all about to have a first course of gun.

Trainum took the empty seat in front of the gun, opposite Missy. Garrett remained standing, covering Trainum's back. Cooper tried to control the situation. He told the detectives they could view the serial number on the gun but that was it. He had apparently changed his mind about giving up the gun. "I do not want you taking my weapon," he said. Trainum had a quick comeback. "Sir, that is not your weapon," he said. Cooper: "No, it's my wife's weapon . . . Missy -- and I'm stating that the gun should not legally leave the house." Trainum: "Mr. Cooper, you have no control over this gun." Trainum, still seated, reached out, took the gun box and closed the cover. "I've taken this weapon because it's going to be possible evidence."

Missy started getting agitated. Someone in the room yelled that Carl should call his lawyer. Cooper disappeared.

This was gut-check time. Both detectives thought Cooper might be getting a gun. Trainum had to stay seated and act as if the temperature in the room was unchanged. Garrett, standing, slid his hand under his coat and onto his own 10mm Smith & Wesson. Trainum's fleeting thought was the hope that Garrett would be quick enough on the draw.

Cooper walked out with a video camera with the lights on and the tape running. "Hey, Cooper, shut that off," Garrett said.

"This is our house," Cooper said.

"We're police officers," Garrett said. "I'm telling you to shut it off."

Cooper did as he was told. Missy started crying. Garrett tried to calm her. The FBI agent waiting outside heard the commotion and walked in. He told Cooper that Trainum and Garrett could take the gun without a warrant. Cooper said: "Uh-uh. I want a warrant. I want a P.G. uniformed officer in here." He called 911. "I have a District officer here trying to take a weapon out of a Maryland residence without a warrant," he said into the phone.

Finally, a Prince George's officer showed up and told Cooper the detectives had a right to take the gun. That dumbfounded Cooper: "How -- how does a District officer have jurisdiction in -- in Maryland to take a weapon?" The officer: "When they work with the FBI there's an interstate task force." Trainum and Garrett left with the gun.

Ballistics tests revealed that a bullet fired from Missy's gun did not match the bullet fired into Officer Howard. The detectives guessed that the barrel had been removed and switched with another gun's, altering the identifying grooves on the slug. That might have made whoever did it confident enough to give up the gun for testing. But ballistics involves more than just marks on slugs. Firing pins and ejectors also leave marks -- on shell casings. The marks on Missy's shells matched the marks on the casings left in the Howard shooting. Cooper was sly, but not sly enough. They had him now, a slam-dunk case. Pressure began to build from Prince George's and D.C. police officials to arrest Cooper immediately and get him off the streets. The detectives resisted it. They still didn't have him for Starbucks.

Garrett and Trainum kept up the tickles, hanging around Cooper's neighborhood where they knew he would see them, interviewing people close to him and subpoenaing some of them to testify before a federal grand jury. A lawyer hired by the Coopers called Homicide and complained. When the Birthday Girl got her grand jury subpoena, the detectives instructed her to call Cooper and read it to him. Tweak, tweak.

The Barber

Over time Garrett and Trainum had come to trust the Birthday Girl and found her useful as a sounding board for Cooper's mood. By January 1999, she told them he was ready to "snap." He believed his phone was tapped and he was being followed. He believed Man, his best friend, was snitching. He had been fired from Wang because they suspected him in an office burglary. Everything was coming down. Only concern for his son kept him from doing what he wanted to do. What was that? She quoted his answer: "I'm going to shoot the two m -- -f -- - who are torturing me."

The detectives still had a card to play. They had the Barber jailed on an arrest warrant for the string of armed robberies the Surgeon's Daughter had described to them from prison. After hours of interrogation, the detectives concluded that the Barber had basically gone straight. Eventually he agreed to cooperate. He told them that Cooper had talked to him beforehand about robbing Starbucks that night. But he never got the message that the robbery was on, he said, so he thought Cooper had done the job alone. That fit with what the detectives knew about both men and had picked up from another informant's tape-recorded chat with the Barber.

Cooper's conversation with the Barber meant the detectives could now link Cooper to Starbucks on a conspiracy charge. But that wasn't enough. They wanted him for the murders themselves.

If Cooper had acted alone as the Barber said, it was the detectives' worst nightmare. That meant no witnesses to the killings -- ever. With no physical evidence, that left only one route to solving Starbucks: Cooper had to implicate himself, either on tape with an informant or in a confession.

On February 25, 1999, Garrett outfitted the Barber with a tiny Nagra tape recorder, a transmitter and a tape of the TV show "Hard Copy" about the Starbucks murders. The tape would be the Barber's excuse for bringing the case up with Cooper. At Cooper's house, the Barber told a story about taping the segment on his TV and suddenly recognizing "this Bama" -- slang for a cop -- he had seen parked on his block. He played the tape. Over the sounds of "Hard Copy," Cooper could be heard pointing out first Trainum, then Garrett, as their faces appeared on his TV screen. But when the Barber brought up Starbucks, Cooper brushed him off, in a conversation hard to hear on the tape. "Man, [inaudible] talking about -- man, that Starbucks s -- -. No, I ain't say nothing." Cooper had eluded them again.

Afterward, the Barber made the detectives a new proposal. He wanted to go back at Cooper and tell him that Trainum and Garrett had rousted him in the street and he had shot it out with them. If he was desperate and on the run, the Barber said, Cooper might relax and start talking. "Let us play with that," Garrett said. The detectives were starting to like this guy.

Three days later, the Barber called Cooper and said it was urgent. This time, the two of them drove around Cooper's neighborhood in the Barber's bugged car. Garrett and Trainum just that day had surprised him on the street, the Barber said, to talk about "some racketeering s -- -" he and Cooper had done in the past. They knew all about the robbery gang. "The Bamas coming out the woodwork with everything," the Barber said. They could link Cooper's "nine" -- Missy's 9mm -- to Starbucks. "Bamas pulling the Georgetown on me," the Barber said.

Cooper stayed cool. They already had "my nine," he said. "If they had any leads that would hold up in court, would I be out?" But how, the Barber asked, did they link them to Starbucks in the first place? Cooper: "I don't know. I don't care. Because as my, as my hand to God, on my father's grave, on my son's life, I had nothing to do with the Starbucks s -- -."

The Barber told Cooper they had his fingerprints inside Starbucks. Cooper shrugged it off. "That's a place of business," he said. "I done been in the m -- -f -- -."

But Cooper had called him about robbing Starbucks that night, the Barber said. "It ain't no crime to think about s -- -," Cooper said.

What about conspiracy? the Barber asked. "They said it's conspiracy."

For conspiracy, Cooper said, you had to go "through the motions about doing something." He used Trainum as an example. "I want to kill him, you see what I'm saying?" Yeah, the Barber said. "Now, they can't arrest me off conspiracy because I want to kill Trainum" because, Cooper said, he had done no planning. "I have not gone down to headquarters, okay?" he said. "I haven't followed him to his house."

Cooper kept playing the street lawyer. They couldn't use his gun against him because they didn't have a warrant. He had talked to a lawyer. "You can't prove that I did s -- -," Cooper said. "Only way you can get me is by word of -- I mean, is by my own admission, that I myself have said, yeah, I did this ... That's the only way they can ever get me for anything."

Cooper talked about the Starbucks victims. "And I actually feel for them, you know, the family and s -- -," he said. But he could not be linked to the crime. "That ain't my style, you know what I'm saying?" He had put crime behind him. "Let me -- let me put it to you like this, you all. All right, man, I'm married, dog. I got a beautiful 3-, almost 4-year-old son ... I am actually a decent law-abiding citizen now, okay? ... I've lived my life of crime. I've done my dirt. I'm trying my hand at being right, and it's started to work for me."

This was more than a little ironic. With the Barber in tow, he had cased a place for a robbery right after Starbucks, and he was now the leading suspect in the burglary and theft of several computers at Wang.

Cooper couldn't stop talking about Trainum and Garrett. Evidently they were under his skin. "Now, the FBI guy, he ain't never come out the mouth and said nothing to me wrong. That Bama been quiet the whole time. Okay, he a little tricky m -- -f -- -. Okay, but he ain't never disrespected me or my wife." But Trainum "has shown a blatant disrespect for me and my family." Cooper said he had "issues" with Trainum that he would solve, "one way or the other." If Cooper were "petty," he said, he would take time off work and follow Trainum home. "Kill up his -- you know what I'm saying, kill his family and then just wait in the house for the n -- - to come home off work, hey honey, I'm home. Pow, pow, pow." But Garrett was different. "I kind of like the Bama," Cooper said. "And cuz cool." "Cuz cool as s -- -," the Barber said. "He don't never say nothing," Cooper said.

He told the Barber that he had once followed Garrett as he walked across a parking lot downtown. "He ain't see me. You see what I'm saying? But I ain't ever had no problems with him ... Now, I have to admit, if it would have been Trainum that I was walking behind, the outcome would have been different ... Trainum is -- I mean, he on my s -- - list. Ain't nothing he can do for me but -- except die slowly."

That was enough. They didn't have Cooper yet on Starbucks. But they had to end it now.

The Endgame

The next day, March 1, 1999, Garrett and another FBI agent met Cooper as he pulled up in his car outside his house in the early evening. Garrett said hello, shook Cooper's hand and told him he was under arrest. Cooper had his son with him, and Garrett arranged to put the handcuffs on after the boy went into the house.

Cooper thanked him for that.

Garrett picked Cooper up on a warrant for the shooting of Officer Howard in Prince George's County. Because the arrest was in D.C., Cooper would have to make a first appearance in D.C. court in the morning before he could be extradited to Prince George's. That meant a night in the D.C. jail, and a chance for Garrett and Trainum to talk to him, if he was willing. Garrett would do the talking, they decided, because Cooper thought he was "cool."

Cooper waived his right to an attorney. He had always been able to talk himself out of trouble. In an interview room at the FBI's Washington field office, he and Garrett began a long psychological dance. Cooper freely talked about Starbucks. He didn't do it. He was willing to take a polygraph.

Cooper's fingerprints hadn't been found in Starbucks, but the detectives knew from his taped chat with the Barber that he thought they had. Garrett used the misconception to telling effect: How did Cooper explain his fingerprints inside Starbucks? Cooper didn't have an answer. His cool started showing cracks. After three hours he got emotional and despondent, weeping softly and saying, "I'm in it for life. I'm in dirt ... You're gonna charge me with Starbucks. I didn't do it."

He made no admissions. And he took back his offer to take a polygraph. After nearly seven hours of questioning ending at 3:24 a.m., they ran out of time. Brad Garrett, the man who had gotten two fanatical terrorists to confess, hit a wall with Carl Cooper.

The next day, Cooper waived extradition and two Prince George's detectives took custody of him. And Garrett took off with his girlfriend on a long-planned ski vacation. But not before he was beeped by Trainum. "Carl is starting to talk," Trainum told him. Cooper had been chatty with the Prince George's detectives on the ride over, and he was starting to crumble. Garrett had broken too many promises to his girlfriend, postponed too many things, not to get on the plane. Trainum kept beeping him, giving him updates. Garrett flew all the way to Colorado before he decided to turn around and come back to D.C.

The Prince George's police detectives talked to Cooper in a room with carpet on its floors and walls and padded chairs. It was an almost cordial atmosphere, with everyone on a first-name basis. Over his 61 hours and 41 minutes in custody, the cops served him spaghetti and meatballs, a McDonald's double cheeseburger and fries, and chicken-and-rice soup. One detective shared a turkey sandwich with him. Trainum was there, waiting outside, watching with a slightly helpless feeling. He had done all he could. The case was now in the hands of others. Garrett did not arrive for many hours.

When he first got to Prince George's, Cooper, visibly upset, was eager to talk about Starbucks and how Trainum was trying to railroad him. Sgt. Joe McCann brought up the Officer Howard shooting. Didn't Carl know that they had ballistic evidence tying him to the crime? Carl was quick with a comeback: Trainum and Garrett had switched the barrel to set him up. No, McCann said. That was not the evidence. It was not the grooves in the barrel but the marks left by the firing pin that tied the gun to the crime.

Cooper didn't have a quick response to that. But soon the admissions began to pour out. His first written statement came within the first few hours: at 4:37 p.m. on March 2. His seventh and last came at 4:35 p.m. on March 4. In between breaks for food and about 20 hours of sleep, he admitted to everything except the murder of Montee Goodman, which he blamed on his old partner Man. In writing, he waived his right to a lawyer numerous times.

It was as if Trainum and Garrett had been psychologically tapping on him for over a year, leaving him ready to crack at one strong blow from Prince George's.

A classic psychology had taken hold. Trainum and Garrett had become the bad cops, and Prince George's police the good cops.

"Every time I tried to talk to Det. Trainum, he treated me like s -- - and harrassed [sic] my family," Cooper wrote at the very end of his Prince George's interrogation. "If he would have shown me he respected [me] as a person, like P.G. did, this would have been over a long time ago."

First, he admitted to shooting Officer Howard, making it sound like a Peeping Tom incident that got out of control, forcing him to fight the officer in self-defense. The gun went off accidentally, he said. Then he talked about the earlier robberies, blaming them on Man and the Surgeon's Daughter and giving himself only a minor role.

Near midnight, Cooper, who had once again requested a polygraph, was given a computerized voice stress test. When the Prince George's detectives told him he showed deception on questions about Starbucks, he began to breathe heavily and sweat. At one point, McCann mentioned that one of the Starbucks victims knew a man Cooper knew. Cooper seized on this and said that the man had done the robbery while Cooper had waited outside as the driver. Then he shifted and said he went inside with the man and an accomplice, who did the shootings while he was in another room. The man he fingered was arrested, but quickly eliminated as a suspect -- he had been shot several times and was a virtual invalid at the time of Starbucks. Confronted with this, Cooper broke, finally and completely. "Sit down, Joe," he said. "Let me tell you." He told McCann that he had in fact acted alone. "I've wanted to admit this ever since it's happened," he wrote in his final confession. "It had to be known."

He said he had planned the robbery for a month. He went inside early that Sunday, after dropping his mother off at church. He wanted to make sure that business was good. He noticed there were no cameras, and he figured, correctly, that the store would not deposit its cash until Monday morning. He called the Barber, alerting him to the possibility. Later, he beeped the Barber, who did not respond. So he decided to go it alone, because he didn't want to miss his "window of opportunity."

Cooper said he entered with two guns, met some resistance from Caity and fired a warning shot. Caity ran to the hall, where he ran after her, struggled with her and shot her. Then he shot the other two. "Everything else is like a dream," he wrote. "It's me but it isn't me doing these things." The specifics were chilling: "I tasted the girl's blood in my mouth." Caller 234 had been very close to the truth. So had Garrett and Trainum.

On March 5, 1999, a year and eight months after the Starbucks murders, the news broke that the case had been solved: Carl Cooper was being charged with three counts of first-degree felony murder while armed. Five months later, he was named in a federal RICO indictment that consolidated the murders with four armed robberies.

Cooper later said his confessions had been coerced. In court, his lawyer called them "the product of extended interrogation, unlawful interrogation, deceit and trickery," and argued that they should not be allowed as evidence against him. But the judge ruled against Cooper, finding he had "an easy, comfortable, familiar, confident attitude towards his interrogators."

After U.S. Attorney General Janet Reno announced her intention to seek the death penalty, Cooper pleaded guilty on April 25, 2000. He was sentenced to life without parole.

Since Starbucks, Garrett has moved on to the Chandra Levy and sniper investigations; he elicited John Lee Malvo's alleged confession. Trainum works on his own, examining a series of unsolved murders and surveying D.C. prostitutes who have been sexually assaulted, looking for patterns. But the two haven't worked together officially again.

They have kept in touch with the Barber and with the Surgeon's Daughter, who just got out of prison. This summer, the detectives plan to attend the Barber's wedding.

Note: This article is based on police and court records and more than a dozen interviews with Trainum and Garrett. Some individuals are not named because they became police informants.

Jeff Leen is The Post's investigations editor. Det. Jim Trainum and FBI agent Brad Garrett will be fielding questions and comments about this article at 1 p.m. Monday on www.washingtonpost.com/liveonline.