On a cloudy morning last May, Karen Ann Robb, 25, discovered an Arlington police boot on her car, tried to kll herself in a gas oven and then was arrested for felony possession of cocaine by Arlington police who had come into the house to help save her life.

Robb, who never had been arrested before and who had never before attempted suicide, now faces a possible prison sentence in Virginia of one to 10 years because a policeman allegedly found half a gram of cocaine in her purse.

The police search that led to the alleged discovery of cocaine was an unjustified "investigatory snoop" that has led to an "outrageous" prosecution attempt according to Robb's defense attorney, Jonathan Shapiro of Alexandria.

Assistant Commonwealth Attorney Karen A. Henenberg disagrees. The search was legal and proper and has led to a prosecution effort that is "in the best interest of the Commonwealth of Virginia," in her view.

The affair has cost Robb, who works as an office manager for a Capitol Hill real estate company, $2,500 in legal fees. She says it also is a reminder of her depression at the time of her suicide attempt.

On May 3, Robb said she was staying at her boyfriend's house near Crystal City in Arlington. She had an ugly argument with her boyfriend that morning, she said, and she had been depressed about her family and her work for a week.

"I'd just dropped out of school at the University of Maryland because my grades were bad and I was thinking that morning about jumping off the Key Bridge. But I couldn't drive because the cops had put a boot on my car," Robb said.

She said she went back into her boyfriend's house, which was empty, and went to the kitchen where she turned on the gas and stuck her head in the oven.

"I was living in the District of Columbia then and I couldn't buy a gun," she said.

Robb had passed out with her head in the oven when a Danish house painter, painting her boyfriend's house, came into the kitchen for a cup of tea. He called police and the Arlington rescue service.

As rescue personnel revived Robb on the kitchen floor, police tried to ask her what her name was and whether she had any identification. "I was being belligerent and bitchy" as she regained consciousness, Robb said. Police claim Robb told them to check her purse for her name, but Robb said she does not remember saying that.

Assistant Commonwealth's Attorned Henenberg said a policeman found Robb's brown purse in the living room and opened it to find a check book with Robb's name and address. The policeman also allegedly found a grey and black film cannister with a razor blade and half a gram of cocaine.

"I'd forgotten all about the cocaine," Robb said."A friend of mine had given it to me to help me stay up all night because I was going through some problems."

Possession of any amount of cocaine, a controlled substance that is used by many young professional people for the mild, temporary euphoria it produces, is a felony in the state of Virginia.

Robb said the first thing she remembers after passing out in the oven is police reading her her rights and later driving her to the Arlington County police station.

After a night in county jail, Robb was released on $1,000 bail. She was indicted by an Arlington grand jury on June 19, and on Sept. 7 her attorney will go to court to try to suppress evidence found in the search of Robb's purse.

"This is a case that cries out to be dropped," said attorney Shapiro.

"I'm sworn to enforce the law," said prosecutor Henenberg.

The two attorneys have, in Henenberg's words, "tried to negotiate the case in a way that would take into account the somewhat unfortunate circumstances."

Henenberg has offered to allow Robb the option for first offenders under Virginia drug law of pleading guilty and going on probation for a year. Shapiro has rejected the offer.

"I don't want my client to live under a cloud for a year," Shapiro said.

Henenberg said the purse search was justified because Robb allegedly gave the policeman consent to find her name and because the "emergency situation" convinced the policeman he should search Robb's purse for any drugs she may have taken as part of her suicide attempt.

Shapiro rejects both arguments, saying that once the policeman found Robb's name on the checkbook he had no further "consent" to continue searcing her purse.

The emergency situation, Shapiro said, had ceased to exist by the time the policeman allegedly found the cocaine. Rescue workers had by that time announced that Robb would recover, Shapiro said.

Robb, who now lives in Camp Springs and plans to return to college when she pays off her legal bills, said the prosecution seems peculiar to her because so many of the people she knows use cocaine far more often than she does.