The DNA testing proved a match to another man, whom Ware said has since confessed to the crime and implicated an accomplice. That accomplice has also confessed, Ware said.
Neither, however, can be prosecuted because the statute of limitations has expired. Both are free, although one is on parole, Ware said.
"Technological advances in science have proved another Dallas County man's innocence and identified the actual perpetrator, but because the statute of limitations has run on these offenses, the State cannot prosecute the two men who did this 16 years ago," Dallas County District Attorney Craig Watkins said in a statement. "It is a gross understatement to say that we are displeased with the fact that we cannot seek justice for the victims in this case because of the laws back in 1992."
Telephone messages left for Waller's attorney were not immediately returned Thursday night.
The abduction happened in March 1992, when two men abducted a couple at gunpoint in the couple's car and made them drive to an ATM, where they stole several hundred dollars. The men then made the couple drive to another site, where both men sexually assaulted the woman after tying up the man, Ware said.
Another couple drove up to the scene and were also held up at gunpoint. But before they could be harmed, a security guard arrived and scared off the men, who fled in separate cars, Ware said.
Three of the four people abducted picked Waller's photo out of an array shown to them by police. The fourth did not identify Waller in the photo array but later picked him out of a live lineup, Ware said.
Waller maintained his innocence and presented an alibi at trial, but was convicted and sentenced to life in prison.
In 2001, Waller became the third Dallas County man to request post-conviction DNA testing under a new state law. The DA's office, then under different leadership, opposed the request and it was denied by a judge, Ware said.
"It was an appropriate case for testing in 2001," Ware said. "Had he been tested back then, then the actual perpetrator could have been identified and could have been prevented from paroling out."
Waller had better luck under Watkins, who started a program last year in which his office works with the Innocence Project of Texas to review hundreds of cases in which jailed inmates have requested post-conviction DNA testing.
Counting Waller, DNA testing has proven the innocence of 19 Dallas County men since 2001, which is a national high, according to the Innocence Project, a New York-based legal center that specializes in overturning wrongful convictions. Texas leads the nation with 33 such exonerations.
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