A Collin County court has dismissed the capital murder case that put Michael Blair on death row for the 1993 killing of Ashley Estell.

The ruling marks an end to more than a decade of legal appeals, but it does not end the search to find out who lured the 7-year-old girl from a Plano park and strangled her.

The Collin County District Attorney's Office and the Plano Police Department are reinvestigating the 15-year-old case that prompted a series of legal reforms known as Ashley's Laws.

In an Aug. 25 motion to dismiss, the district attorney noted the Texas Court of Criminal Appeals had overturned Mr. Blair's 1994 conviction because new DNA testing had undermined certain evidence presented in the trial.

"It has been determined that this case should be dismissed in the interest of justice so that the offense charged in the indictment can be further investigated," according to the motion that was granted by state District Judge Greg Brewer.

Ashley's mother, Diana Estell, declined to comment Tuesday on the dismissal of the case.

In 1995, she and her husband, Richard, filed a lawsuit against the state, claiming that officials were negligent in their supervision of Mr. Blair, who was on parole at the time of Ashley's death. The case was later dismissed, according to the Texas attorney general's office.

The cold case investigation will examine any new evidence or possible suspects, including Mr. Blair, said Mary Scanlon, chief of the district attorney's family justice division and one of the prosecutors assigned to the new investigation.

"We haven't conceded that he's innocent," she said of Mr. Blair, who has consistently denied responsibility for the crime.

Despite the dismissal, Mr. Blair is expected to remain behind bars for the rest of his life. He is serving four life sentences – three of them consecutive – for sex crimes against children that he confessed to in 2004.