A Bridgeport man who considered and rejected a sleepwalking defense will go on trial Tuesday in New London Superior Court for attempting to rob an 81-year-old woman with a knife in a parking garage at Mohegan Sun casino in March 2012.

Winston A. Riley, 28, has pleaded not guilty to first-degree robbery, attempted first-degree robbery, second-degree threatening, first-degree reckless endangerment, attempted second-degree larceny and carrying a dangerous weapon.

State police said he attempted to snatch the victim’s purse in the casino parking lot. The woman resisted, and Riley fled. He was caught a short time later.

Riley is represented by attorney Tina Sypek D’Amato, who practices law with her husband, Nicholas D’Amato, in Bridgeport. Shortly after Riley’s arrest, Nicholas D’Amato said he may pursue a medical defense, since Riley has a history of sleepwalking. Sypek D’Amato said this week that she will not use the sleepwalking defense at trial.

Riley’s attorney said he had no criminal history before his arrest. He has been free in lieu of $85,000 bond while his case was pending.

Senior Assistant State’s Attorney Stephen M. Carney is prosecuting and is expected to introduce video surveillance of the incident into evidence.

Judge Arthur C. Hadden is presiding at the trial, which is expected to last through Friday, May 17.