The young East Baltimore woman gave police a vivid description of her rape: A man snatched her off the street and used a pocketknife to force her into the darkness of Ellwood Park.

Then the pregnancy test conducted during her medical examination came back positive. Police grew skeptical and confrontational. The details of her story changed with each telling.

"They started making it seem like I had cheated on my boyfriend, got pregnant and wanted to hide it," she said recently as she hugged her son, now 9 years old. "I guess my details weren't as good as they were the first night."

The woman stopped cooperating, and police classified the case as "unfounded," meaning they found the woman's report to be baseless.

But it wasn't.

Last year, Lawrence Mosley, a Baltimore man behind bars for another crime, was convicted of raping the woman, who was 19 at the time of the December 2000 attack.

Not only did the woman testify in court, but DNA evidence from her rape kit — which had been kept and catalogued for nearly a decade even though police didn't believe her — was central to the trial.

Mosley's DNA also matched evidence from the kit of another woman who had been attacked two days earlier under similar circumstances, according to police reports.

The case of Lawrence Mosley and his victims is perhaps the most troubling illustration to date of the way Baltimore police handle some claims of rape and sexual abuse.

A Baltimore Sun analysis of federal crime statistics showed that for the past four years, Baltimore has led the nation in the percentage of rape cases that police say are false or baseless. Many victims of sexual abuse say police interrogators ask confrontational questions and challenge their motives and veracity; as a result, many women decide not to cooperate, leading to the cases being shelved.

The Sun's analysis also shows that four in 10 emergency calls on sexual abuse never make it to detectives specializing in sex crimes, having been dismissed by police officers at the scene.

Police initially defended their practices. But after reviewing the analysis, Mayor Stephanie Rawlings-Blake called for an audit into all such "unfounded" cases, which began earlier this month. Rawlings-Blake and Police Commissioner Frederick H. Bealefeld III also announced the creation of a hot line for victims to share their stories of interacting with police or to request that their cases be reviewed by the audit committee. More than two dozen cases reported to the hot line will be reviewed by the committee.

The commissioner also announced last week that officers will no longer be allowed to reject calls on the spot without a more thorough review.

Advocates for sexual abuse victims say Baltimore police have taken a wrong approach to rape and similar crimes, demeaning those who say they were accosted in an apparent effort to weed out cases where those making the claims might be lying.

The two women attacked by Mosley experienced that firsthand, according to them and their family members. The Sun does not, as a matter of policy, name victims of sexual crimes or provide the names of family members through which they might be identified.

In the first case, the woman attacked in Ellwood Park said that in the days after making her initial report, she put forth her best effort to recount details that detectives were seeking: whether her attacker took off her clothes or she removed them herself; whether she was walking to her boyfriend's or cousin's house when the attack occurred; whether her rapist had used a condom when he forced himself on her.

But she said detectives focused on inconsistencies.

"No matter what I said, they kept saying, 'Well, the other night you said this,''' the woman said. So she stopped participating in the investigation. "After that, I didn't go back."

Two weeks later, her case was reclassified as "unfounded."