A convicted killer serving life behind bars when he staged a daring escape from a maximum-security prison has plead guilty to criminal charges for the breakout.In 35-year-old David Sweat's second court appearance since his capture in June of 2015, he no longer wore a sling from his gunshot injuries, his head was shaved and he politely answered a series of questions from the judge.  Sweat has been in solitary confinement at Five Points prison. He pleaded guilty to two felony counts of first-degree escape and a felony count of promoting prison contraband for possessing hacksaw blades used to cut his way out. He escaped June 6th from Clinton Correctional Facility with Richard Matt, another convicted killer. Matt was shot dead June 26th. Sweat was shot and captured two days later.