Update 1: Suspect in Washington Cop Killings Was Out on Street Despite Lengthy Rap Sheet, Sentences

As the suspect in the ambush execution of four police officers remains on the run, questions are swirling as to how and why Maurice Clemmons — an ex-con who at one time faced more than 100 years behind bars — was allowed to live free.

Clemmons, 37, of Tacoma, Wash., has an extensive, violent criminal history marked by volatile and unstable behavior, according to court records and news reports. His criminal history includes at least five felony convictions in Arkansas and at least eight felony charges in Washington, according to the Seattle Times. He had a lengthy prison sentence commuted in 2000 by former Arkansas Gov. Mike Huckabee, who cited Clemmons' youth.

"Should he be found to be responsible for this horrible tragedy, it will be the result of a series of failures in the criminal justice system in both Arkansas and Washington State," Huckabee said in a statement issued Sunday. The former governor, who ran for president in 2008 and has been a leading contender in polls for the 2012 Republican nomination, currently hosts a show on Fox News Channel.