A drunk driver who struck and killed a 33-year-old bicyclist July 4, carried her on the car's hood for nearly a half-mile, then dumped her body and fled was sentenced yesterday to one year in the Montgomery County jail after a plea bargain that angered the victim's family.

"I'm very angry at everyone," said Jo Anne Royle, the mother of the victim, Robin Royle. She said the actions of the driver, David Henry, 24, of Mount Rainier -- who could have faced up to 11 years in a state prison -- were "so despicable, so callous. He just dumped her face-down, not even caring if she needed any medical attention."

But county prosecutors said they opted to deal with the matter the way most cases are handled, through plea bargaining, in part because the prosecution believed that it had a less-than-airtight case against a man with no previous conviction.

In exchange for Henry's guilty plea, the state's attorney's office recently agreed to drop several other charges and guaranteed that Henry would serve no more than three years in jail on charges of manslaughter by motor vehicle and driving while intoxicated.

Henry, who conceded in court yesterday that he is an alcoholic with a history of cocaine and marijuana use, was sentenced by Circuit Judge William C. Miller and will be eligible for parole in three months.

The prosecutor, Assistant State's Attorney Ann Harrington, gave the judge about 30 letters urging a stiff sentence for Henry.

"I'm not going to be stampeded into any kind of lynch mob justice," Miller said. " . . . There's no question there are other David Henrys out there, and I am afraid whatever I do here isn't going to change that."

Harrington said that she decided to plea-bargain because she was far from certain of winning a conviction, regardless of how strong the evidence against him seemed to the victim's family.

The prosecutor said questions would have emerged in a trial about how recklessly Henry was driving, how intoxicated he was and whether he could have avoided Royle, who was bicycling in darkness at 1 a.m. on a busy section of Rockville Pike without reflective clothing.

Royle, a California native who owned a condominium in Northwest Washington, was a paralegal at the D.C. law firm of Sullivan & Cromwell and also worked for a travel agency, guiding tours to the Soviet Union a few times a year, according to her boyfriend, John Burns. She was an honors graduate of George Washington University, where she learned to speak Russian, he said.

Royle had lost about 130 pounds by dieting in the last year of her life, Burns said, and she had taken up bicycling to strengthen her legs.

About 1 a.m. on the Fourth of July, police said, she was pedaling south on Rockville Pike, just past the busy intersection of the Pike, Rte. 270 and the Capital Beltway.

Henry, a bartender who was then living with his mother, was headed in the same direction, driving his girlfriend's 1979 Pontiac Bonneville, according to his attorney, Mitchell Rubenstein.

Henry is a high school graduate and a drummer who studied for two years at the Berklee College of Music in Boston, Rubenstein said. He said his client had visited two Rockville bars that night, had consumed about a half-dozen drinks and was on his way home.

He was driving in the far right lane and missed the Beltway exit off Rockville Pike, the lawyer said. The road, five lanes wide at that point, narrows to two lanes after the exit. Henry fixed his attention on a car to his left as he attempted to merge in that direction, Rubenstein said. He said that Henry did not notice the woman on the bicycle in front of him.

She tumbled onto the hood as the Pontiac struck her. To Henry, "it was a horrible sight," Rubenstein told Judge Miller yesterday. "Probably something right out of a horror movie."

Henry traveled four-tenths of a mile before turning into a Goodwill Industries driveway, the lawyer said. He dragged Royle off the hood. "And for reasons that we cannot explain to the court, other than that he was totally freaked out, he left the body and took off," Rubenstein told Miller. At least one witness noted the car's license number.

A police officer stopped and arrested Henry within minutes a few miles away. Henry took a Breathalyzer test that showed his blood-alcohol level at 0.15 percent, Rubenstein said. By law, he said, a person who produces a reading between 0.08 and 0.12 percent is considered "under the influence," and a reading of 0.13 or above means "intoxicated."

On Aug. 6, Harrington said, a county grand jury indicted Henry for manslaughter by automobile, homicide by automobile while intoxicated, driving while intoxicated, leaving the scene of an accident, possession of marijuana and possession of cocaine. By then, she said, she and Rubenstein already had begun negotiating pleas.

To prove the most serious charge -- manslaughter by automobile, which carries a sentence of up to five years -- Harrington would have been required to show that Henry acted in a "gross, wanton, negligent manner," she said. Showing only that Henry was marginally intoxicated may not have been enough to meet that standard, she said. He was not driving recklessly at a high speed or driving on the wrong side of the road, she noted.

As for the charge of homicide by automobile while intoxicated, Rubinstein said, "There are a lot of ways to knock 'intoxicated' down to 'under the influence.' " He said he would have called several experts to testify about the Breathalyzer's "margin of error," raising a question about whether Henry's 0.15 reading was accurate.

As for the drug charges, Harrington said, police found only trace amounts of marijuana and cocaine.

To avoid the uncertainty of a trial, Harrington said, she agreed to a plea bargain, a practice common in an overburdened legal system. She wanted Henry to plead guilty to the most serious of the criminal charges, manslaughter by automobile, and the most serious of the traffic violations, driving while intoxicated.

To spare his client that same uncertainty, as well as the expense of expert witnesses, Rubenstein said, he recommended that Henry agree to the deal.

"I think it's fair to both sides," Harrington said.

Judge Miller approved the plea bargain in September, agreeing to no more than three years of confinement for Henry.

The judge yesterday sentenced him to five years for manslaughter by automobile but suspended all but one year of the term. He sentenced him to a concurrent one-year term for driving while intoxicated and ordered Henry to undergo psychological counseling and treatment for alcohol abuse during a period of probation after his release.

"I feel ghastly," said Jo Anne Royle, who traveled here from her home in California for the sentencing. "But there's nothing I can do. It's how the system worked. You move things along."