Walter and Reecie Piechowicz were awaiting the arrival of their son, Scott, at a Montgomery Ward store in Laurel when they first found out something was wrong. It was 6:30 p.m. when they were informed by a voice over the store loudspeaker that someone urgently wished to speak to them at the front counter.

The visitor was a Prince George's County police officer who told Walter Piechowicz that his son was en route to the Baltimore Shock Trauma Unit and urged the couple to get to the hospital as fast as they could. Reecie Piechowicz thought her son, a hotel manager in Pikesville, had been in an auto accident.

But 45 minutes later, the couple discovered that Scott and his 19-year-old sister-in-law, Susan Kennedy, who were scheduled to testify as federal prosecution witnesses in a drug conspiracy trial in Baltimore, had been machine-gunned to death at the Pikesville hotel in an underworld-style slaying.

"Ever since that day I've been trying to understand why," Walter Piechowicz said, tears welling in his eyes as he sat in his Riverdale home. "Scott was no saint, but he was an honest, hard-working guy who was man enough to do the right thing. There's no logic in any of this. Absolutely none."

David Scott Piechowicz was a strait-laced 27-year-old Prince George's County native who, his wife said, wanted nothing more from life than to be a good husband, father and hotel manager. Instead, he unintentionally became a witness to an alleged drug conspiracy and may have paid for that coincidence with his life.

His wife, Cheryl, 23, is now being heavily guarded by federal agents at an undisclosed location. She is due to testify this week in U.S. District Court in Baltimore as a prosecution witness in the same drug conspiracy trial in which her husband and sister were to participate.

Prosecutors consider her testimony potentially far more damaging to the defense than that of the two victims. Cheryl Piechowicz said in a telephone interview that the killer's bullets were really meant for her. "I'm still afraid. I think my life is very much in danger," she said. "But I know I have to do this testify --for Scott, for myself, for everyone involved."

No arrests have been made in connection with the killings, despite an extensive search in the Baltimore area by more than 100 federal agents and Baltimore County police. A county police spokesman described the gun used in the killings as an unusual, easily concealed automatic machine gun.

"All we can say right now is that the two people killed were important witnesses in a federal case," said Andrew Manning, spokesman for the FBI field office in Baltimore. "At this point we're also investigating two murders."

Scott Piechowicz and Kennedy were shot about 3 p.m. on April 28. Piechowicz, a graduate of Parkdale High School in Riverdale and the University of Maryland, was on duty behind the desk of the 50-room Warren House Hotel on Reisterstown Road in Pikesville. Kennedy, the daughter of a Baltimore policeman, was working as the receptionist.

Located on a busy four-lane thoroughfare lined with motels and specialty shops in a suburb northwest of Baltimore, the hotel lobby is usually busy weekday afternoons, full of guests and customers visiting first-floor shops.

That day, however, the lobby was apparently empty when a gunman walked to the front desk and fired 17 shots at point-blank range from a .380 caliber machine gun at Piechowicz and Kennedy.

Court records show that Kennedy, Piechowicz and his wife were scheduled to testify as witnesses in the federal trial of Anthony Grandison, 30, a Baltimore man charged with conspiring to distribute heroin and cocaine and possession of a .38 caliber pistol.

Grandison, who pleaded not guilty to the conspiracy and firearm charges and was in jail at the time of the murders, had been investigated by the Drug Enforcement Administration in 1979, when he was convicted of assaulting a DEA agent and sentenced to five years in prison.

Last year, Grandison was released on probation. The charges in his current trial, which began Friday, stem from his arrest Nov. 8 by federal agents for a parole violation. On his arrest, agents found Grandison in possession of a key to room 219 at the Warren House Hotel, according to court records.

The records show that shortly thereafter three people were observed attempting to break into that room. When confronted by manager Piechowicz, one of the people, a woman, said she was the occupant's sister, that the occupant had been arrested and that she wanted to retrieve his belongings from the room.

She gave Piechowicz a phone number to verify the arrest. The phone number, however, was that of the FBI. An agent answering told Piechowicz to remove the articles from the hotel room and hold them until authorities arrived. After obtaining a search warrant, federal agents discovered four ounces of high-grade heroin and a pound of cocaine in an overnight bag, according to court documents.

Weeks later, Piechowicz and his wife, who also worked at the hotel as a desk clerk, were approached by federal agents who wanted them and Kennedy to identify Grandison from a set of photographs. "Scott and Sue didn't have a good memory for faces," Cheryl Piechowicz said, "but I was able to pick him out . . . I remembered him from his time at the hotel."

Cheryl Piechowicz said she never felt afraid during all of this until she, her husband and Kennedy went to testify at a preliminary hearing in the Grandison case several months ago. "I think Scott and I both felt a little guilty in playing a role in sending someone off to jail," she said. "But that changed when we went to testify at the hearing. He Grandison kept giving us these mean, mean looks."

She later expressed her fears to a DEA agent, who gave her his business card, said he lived in their Reisterstown, Md., neighborhood, and could arrive at their home or the hotel "in five minutes" if any danger arose.

"I do feel bitter," she said. "I think we all could have been protected . . . No one ever told us there was any danger involved."

Grandison was indicted on drug-conspiracy charges in connection with the drugs recovered at the hotel. During opening arguments of the Grandison trial Friday, Grandison's attorney, Edward Smith Jr., said he would introduce evidence to prove that neither the fingerprints found in room 219 nor the handwriting of the person who signed the hotel register belonged to his client. Grandison has denied that he ever rented the hotel room.

Assistant U.S. Attorney Ty Cobb, meanwhile, without ever mentioning that Piechowicz had been murdered, told the jury that the hotel manager was "unavailable" and that a tape recording of Scott Piechowicz's testimony at the pre-trial hearing would be played instead. The Grandison jury has been sequestered because of publicity relating to the murders.

The night before the shootings, Cheryl Piechowicz said, she and her husband had stayed up late hanging wallpaper in her daughter's bedroom as a gift for the child's fifth birthday. The next day her husband was to meet his parents at the Montgomery Ward store in Laurel to pick out a set of cabinets for the bathroom of the young couple's home, which they were renovating.

Cheryl Piechowicz said she was scheduled to appear for work at the hotel at 4 p.m. the day of the shooting. Instead, she received a phone call at 3:15 p.m. that day informing her that Scott and her sister had been shot.

"I just don't know where to go from here after I testify," she said. "What do you do when your husband and sister have been killed?"

Last week, Scott Piechowicz was invariably described by friends, colleagues, relatives and former teachers as an honest, straightforward young man who enjoyed tennis, basketball and bowling and was entirely dedicated to his family and work.

"While a lot of other kids were into drugs and stuff, Scotty was different. He was the straightest guy I ever knew," said Richard Miller, a close neighborhood and school friend of Piechowicz. "He was the kind of guy who, when everyone was getting drunk at parties, you could count on to drive you home.

"He was civic minded. I don't know if I could have had the nerve to do something like he was planning to do at that trial, but I can certainly see him doing it."

Barbara Hines, a journalism professor at the University of Maryland who taught journalism at Parkdale High School while Piechowicz was there, remembered him as "the kind of boy you'd want your own son to be like."

"He was tall and thin and sort of shy, but he could brighten your whole outlook on life. He wasn't the type who won a lot of honors, but he was a good student," she said. "You don't want to say the all-American boy because that sounds so trite. But it's so true in this case. He was the boy next door."

Piechowicz, who was the editor of the sports page at Parkdale High School, entered the University of Maryland hoping to become a reporter, his parents recalled. He majored in history, was a member of the Theta Chi fraternity and graduated in 1977. He worked part-time as a bartender at the Elks Club in Riverdale where his father, an industrial engineer at Fort Meade, was a member, and at the Envoy Hotel on New York Avenue NW.

After graduation, he took a full-time job at the Envoy, one of several hotels owned by Joseph Weinberg of Baltimore. In 1979, when Weinberg purchased the Warren House Hotel in Pikesville, he asked Piechowicz to manage it. There he met his future wife, whom he married two years ago.

"Growing up in Washington and all, he didn't have many friends here," recalled his wife. "He devoted himself to me, my daughter and his work and I think his main goal in life was to be perfect in all three roles. He would have been perfectly happy being a hotel manager the rest of his life."

Piechowicz was buried last week at a cemetery in Laurel. At their Riverdale home, Walter and Reecie Piechowicz say they are still trying to understand what happened to their only child and why.

"The police told me they can't say very much about it because so much is still up in the air," said Walter Piechowicz. "They said when everything's over they'll sit down with us and tell us everything they know. I guess Scott just gave his life for something he thought was right."