Kenneth Ray Henry Jr., 28, faces up to 99 years or life in prison if convicted of sexual assault in Bastrop on April 22, 2004. The alleged victim was unable to provide a description or other clues to the identity of her assailant, making the case a rare example of “stranger on stranger” assault, according to prosecutors.

But police investigators collected medical evidence at the time and submitted it for analysis by the Department of Public Safety crime lab in Austin. That analysis yielded a DNA portrait of the attacker–but without a name or face attached, said District Attorney Bryan Goertz.

State prison authorities now routinely take DNA samples from felony convicts, and when Henry was tested as part of the program, a state data base linked him to the old Bastrop case, said Goertz.

Judge Chris Duggan is presiding over the trial in 423rd District Court in Bastrop. Testimony in the case may last no more than one day, said officials.