Outgoing Philadelphia District Attorney Lynne M. Abraham vigorously disputes the use of conviction figures to judge her performance. She says every case is vitally important to the victim - and thus to her prosecutors.

In a 90-minute interview last week, the D.A. was dismissive of The Inquirer's statistical analysis of criminal case outcomes.

"You can make those numbers say anything you want," she said. "Here's how I judge: Every day, this group of people and every person in this office gets up to work ready to serve the public, in an honest, uncompromising fashion. We're there to do justice."

She said any prosecutor intent on polishing his or her image could easily boost conviction rates by refusing to take on difficult cases or giving criminals sweetheart deals in return for guilty pleas.

"I'm so incensed that you do justice by the numbers," Abraham said. "It would be so wrong - it would be so low-rent - of The Inquirer to put a period on the end of my tenure here to say, 'Oh, well, she had a conviction rate of X percent.' "

Abraham, 68, a Democrat, was named the city's top prosecutor in 1991, after serving as a Philadelphia judge for 15 years.

As D.A., Abraham won praise for a devastating grand-jury report on the Archdiocese of Philadelphia and its decades-long cover-up of sexual abuse of children by priests. Her office also issued a blistering report on how the city's Department of Human Services contributed to the starvation death of a 14-year-old girl.

Yet critics have complained that Abraham did not aggressively pursue police misconduct or political corruption.

In questioning the conviction statistics, Abraham and her senior aides were especially critical of federal comparative reports that list Philadelphia as having the nation's lowest felony conviction rate. Court administrators said they, too, were skeptical of this finding.

The latest such report was released last year. Using a sampling of 2004 cases from 39 counties, researchers with the U.S. Bureau of Justice Statistics concluded that Philadelphia prosecutors won convictions in 40 percent of their cases. The national average was 68 percent.

Among other issues, Abraham's aides said, the definition of a felony in Pennsylvania differs from that in other states. They said some jurisdictions in the study had felony caseloads that included property crimes that are not classified as felonies in Pennsylvania. They suggested that this skewed the conclusions.

"The BJS thing, to us, is really not a fair comparison," said Arnold H. Gordon, first deputy district attorney. "It's comparing apples and oranges. The definitions they used do not apply across jurisdictions."

However, the federal study does permit a comparison limited to cities, such as Philadelphia, where caseloads include large numbers of violent felonies. Among this group, Philadelphia's conviction rate remains the lowest.

Abraham and her aides also say conviction rates alone give an incomplete picture of an office's performance - and could mask the widespread granting of lenient pleas elsewhere.

Said Gordon: "This office for many years, even before Lynne Abraham, took the position that we're not going to be part of a downward spiral by negotiating guilty pleas."