From Richard Matt's Wikipedia page:
"When approximately 13 years old, Matt escaped from a group home, hiding in Allegany State Park and taking food and other supplies from vacation homes. He had been remanded to the home for stealing a houseboat."
"In June 1986, he climbed a fence to escape from the Erie County Correctional Facility, where he was serving a one-year sentence for assault. According to retired Tonawanda policeman David Bently, Matt evaded police for four days, hopping a freight train to his brother's house in Tonawanda where he was ultimately apprehended."
"On December 3, 1997, Richard Matt attacked his 72-year-old boss, William Rickerson, in his North Tonawanda home. After attacking him, Matt forced Rickerson into his trunk. Matt believed Rickerson had large sums of money in his possession and demanded to know its location. Later, Matt broke Rickerson's neck with his bare hands. He then dismembered the body and fled New York State to avoid capture."
"Prior to 2007, Matt nearly escaped from a prison in Mexico, climbing to the roof before being shot by guards. According to his son, "He's been shot like nine times. 'It's like they can't kill him.' Matt was turned over to U.S. authorities in 2007. According to court reporter Rick Pfeiffer, the Mexican government placed him without explanation on a plane with a drug kingpin they had agreed to extradite because he had 'been such a difficult prisoner."
"During his trial for the murder of Rickerson, authorities suspected he had a plan to escape from Niagara County Jail. Matt was made to wear a stun belt and snipers were posted outside the courtroom to prevent his escape."
Does anyone else see a pattern? [/sarc]
His criminal history is marked by extremely poor judgment (e.g., stealing a houseboat @13), impulsivity (e.g. stabbing someone he'd just met in a bar), extreme ruthlessness (hands-on brutal murders) and lack of effective conscience. Then there was the pattern of escape attempts.
Clinton is a maximum security prison, so I imagine that many of the prisoners present a higher-than-average escape risk, in addition to greater dangerousness, but I wonder if Matt was among the highest risk prisoners, even within that group.
Incidentally, does anyone believe that Matt and Sweat weren't going to kill the prison guard once she provided them with a car and any cash she had? She wasn't cut out to for life on the run and would quickly become an inconvenience for two violent men running from the law.