BUFFALO, NY (WKBW) - After four days of testimony, the prosecution rested its case in the Luke Wright rape and sodomy trial.
Wright, 32, of North Collins is accused of sexually abusing and torturing his developmentally disabled sister, 32-year-old Laura Cummings.
Laura was killed by their mother on January 21, 2010. Eva Cummings, 51, is serving 52-years-to life in prison.
On Friday morning, a forensic biologist testified that Luke Wright's DNA was found on a hood that prosecutors say Luke used to cover Laura's face.
Thomas Grill, who works in the crime lab at Erie County Police Services said Wright's DNA was also found on pieces of cloth that Wright allegedly used to tie Laura to a kitchen chair.
Wright's DNA was also found in Laura's vagina, Grill said.
Three police detectives testified this week that Wright confessed to having sex with his sister.
Defense attorney John Nuchereno said Wright did not realize the statements he made to police could be used against him at trial.
"You have to consider three very experienced detectives, three on one, and the one is an individual suffering from traumatic brain injury and retardation," Nuchereno said to reporters.
Nuchereno will call Dr. Charles Ewing to the stand on Monday. Ewing, a forensic psychologist, will testify about Wright's mental capacity, said Nuchereno.
"We've gone back many years and provided Dr. Ewing with records that show the traumatic brain injury, that show the mental retardation, that shows that he's been assessed at the functioning level in the lowest one percent of all people walking the face of this country," he said.
Prosecutors say Wright, who was found mentally fit to stand trial by the court, knows the difference between right and wrong.
"It's true the defendant is mildly mentally retarded," prosecutor Kristen St. Mary told the jury during opening statements on Tuesday. "But none of those things make him a victim in this courtroom.
Wright could spend the rest of his life in prison if convicted.