The hardest gangsters and criminals on Death Row say they don't care until they find God. They know they don't want to go to hell, so all that hardcore attitude quickly vanishes.
Example: Ted Bundy. He gave his life to Christ while on Death Row.
Personally, they're smart for giving their hearts to Christ even on Death Row because they know hell is eternal suffering, once you go there, you suffer forever. They want no parts of that.