Effectiveness of DNA Testing Questioned


Richard Willing, USA Today

DNA tests on evidence from thousands of unsolved rapes in two big cities are solving only a small fraction of the crimes, USA TODAY has learned.

The results are the first from private testing of evidence. They raise questions about the cost effectiveness of federal plans to spend hundreds of millions of dollars to test evidence from a national backlog of unsolved sex crimes.

A group appointed by Attorney General John Ashcroft will take up the issue at a two-day meeting that begins next Monday.

New York City, with more than 17,000 unsolved rapes going back at least 10 years, is one of a few jurisdictions that has not waited for federal help to begin the DNA testing. Using $ 12 million of its own money, the city began hiring private labs two years ago to draw DNA from semen collected from rape victims. The DNA is then compared with the more than 1 million DNA samples collected from convicted rapists, murderers and other felons. Those samples are held in state and federal databases.

Present in the nucleus of most human cells, DNA carries a person's unique genetic code.

Of 8,300 rapes analyzed so far, about 148 have been matched to offenders in the database, New York officials said. That's a match rate of less than 2%. Baltimore, which has been performing similar testing since the summer, has tested 140 cases and scored six matches, a rate of 4%. The Baltimore tests are being paid for with $ 700,000 in city funds and foundation grants.

New York officials say they are withholding judgement about the project until spring, when all the old cases have been analyzed. They plan to study how collection procedures can be improved.

The testing "carries the hope of justice for so many women," says Michael Farrell, who is overseeing DNA testing for New York City. "We're not going to draw any conclusions one way or another until we've done it all."

This September, the Senate authorized $ 275 million in federal grants that would pay for DNA tests in unsolved rape cases. The measure is before the House of Representatives.

The Justice Department, reflecting what officials say is Ashcroft's desire to use DNA more effectively in solving crimes, has convened a panel of three dozen lab experts to determine the true size of the backlog of unsolved cases and to recommend solutions.

Results of the New York and Baltimore results have furnished new support for critics of mass testing.

"The (national DNA) system doesn't really do an efficient job of catching sex offenders," says Edward Blake, who runs a nationally known DNA test lab in Oakland.

Supporters of public testing say they are not discouraged by the low number of matches. They note that the DNA drawn from unsolved rapes will remain in computer databases and can be matched against new offenders as they are added to the database.

"Testing isn't the end of the process, it's really just the beginning," says Jennifer Crider, spokeswoman for Sen. Maria Cantwell, D-Wash, a co-sponsor of the legislation to test DNA in unsolved rape cases.

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