Senator Eliot Shapleigh - El Paso, Texas

DALLAS -- Desirée Wood gave up hope that the man who raped her 20 years ago in Dallas would ever be caught and sentenced for the crime. Now, she says, she has reason to believe her attacker might see some form of justice, after all.

On Tuesday, a law takes effect in Texas that lets prosecutors and parole boards for the first time see DNA evidence that links a suspect to an old sexual assault, even though the statute of limitations has expired on the case and the suspect was never tried. Previously, there would be no record linking the suspect to the old crime.

Supporters of the law, the first of its kind in the country, hope it means that suspects in those old cases will face more-vigorous prosecutions and sterner parole boards should they find themselves in trouble with the law again. Opponents say the law could rob suspects of due-process rights.

The change attempts to close a gap created by improved technology and an outdated law. Advances in genetic testing have enabled prosecutors to access even the smallest DNA samples to identify suspects in old criminal cases. But even though the Texas Legislature in 2001 removed the state's five-year statute of limitations on sexual-assault charges, the change doesn't apply to alleged assaults before 2001.

In Ms. Wood's case, the DNA evidence collected after her rape 20 years ago was processed by the Dallas Police Department in 2008 as part of its novel Sexual Assault Cold Case Program, which focuses on cases too old to prosecute.

The results of the DNA test were fed into a national crime database and matched the profile of a Louisiana man who has been in and out of prison for burglary and other small offenses. He has denied to police that he raped Ms. Wood, but under the new law, the DNA results will be attached to his criminal file maintained by the Texas Department of Public Safety.

"The next time he gets in trouble for petty things, the prosecutors will see this guy is a bigger threat," said Ms. Wood, who said she struggled for years after the attack with anger issues and nightmares.

The new Texas law was conceived and championed by a small group of rape survivors who had joined a Dallas Police Department support group launched as part of the city's cold-case project. Reopening old cases also can reopen emotional wounds, and though the women were grateful the police were trying to identify their attackers, for many that wasn't enough.

"The women wanted the men to be held accountable in some way," said Sgt. Patrick Welsh, who runs the department's sexual-assault unit and launched the cold-case program nine years ago.

The ACLU still has concerns about how the information could be used. "This is something we will definitely be monitoring to make sure there aren't negative unintended consequences," said Rebecca Bernhardt, policy director of the Texas ACLU.

The new law, as well as the Dallas cold-case program that inspired it, are unique in the country, according to Lisa Hurst, a Washington-based consultant who has studied DNA forensic backlogs and works with the National Center for Victims of Crime.

"Many crime labs can't get to the stuff they're getting in today, much less 10 years or 20 years ago," she said. "Most agencies will not test the evidence unless the case is prosecutable."

Since 2001, 15 states have passed a DNA exception for sexual-assault cases, extending by several years or indefinitely the amount of time prosecutors have to try a case if DNA testing or other scientific advances can help identify a potential suspect.

Unlike many jurisdictions that destroyed evidence in unsolved cases when the statute of limitations expired, Dallas has retained decades' worth of the blood and semen samples kept in so-called rape kits collected as evidence when someone reports a sexual assault.

But even in other cities that have retained the evidence, laboratories are frequently overwhelmed with hundreds of new cases each year, creating backlogs lasting months or years waiting for DNA results.

So while some prosecutors in other states admire the Texas law, they aren't likely to push for similar changes. "With limited resources, the testing has to come second to that done on cases that can still be tried," said Mitch Morrissey, Denver's district attorney.

Since launching the Dallas cold-case project in 2001, Sgt. Welsh has tested 289 old rape kits dating from 1983 to 1986 and found DNA matches in 23 cases. He is determined to eventually comb through all the thousands of unsolved rape cases before 2001 on which DNA analysis might shed some light.

Before the law was passed, Sgt. Welsh and the victims took the initiative to hold alleged attackers accountable, alerting the Texas Board of Pardons and Paroles to DNA evidence linking a convict to an old assault case. Now, that information will automatically be in a convict's file for anyone in law enforcement to see.

In one case, Sgt. Welsh persuaded the board to alter the terms of one suspected attacker's parole. DNA testing linked a 25-year-old rape case to a man who had been released from prison on a kidnapping charge. When informed of the test results, the board strengthened the terms of parole, requiring the man to visit his parole officer more frequently and attend regular counseling sessions for sex offenders.

"This law could have an impact on an inmate's terms of parole," said Troy Fox, administrator for the parole board. "The board considers all input for conditions it might want to impose on a parolee to protect society."

The DNA testing can cut two ways. Dallas nurse Carrie Krejci thought she knew the identity of her rapist for 20 years, and that he was safely locked away in prison for other assaults. But DNA testing didn't match the man she believed to be her attacker -- or anyone else in the system.

"It made me feel vulnerable all over again," Ms. Krejci said.