Adrienne Shelly by Ron Galella/ WireImage.com Adrienne Shelly by Ron Galella/ WireImage.com

Diego Pillco, the 20-year-old construction worker who in November 2006 killed actress Adrienne Shelly ( Waitress) after she caught him rummaging through her purse - and then tried to make it look like a suicide - on Thursday pleaded guilty to manslaughter, and as such will serve 25 years in prison.

"I just want to ask for forgiveness [from Shelly's] family," Pillco said at the sentencing. In response, Supreme Court Justice Carol Berkman said, "I doubt you'll get that, sir."