I'm tough on religious idiots. I also commented somewhere that you almost always see jailhouse conversions after the criminal has been incarcerated; you rarely see the conversion precede the confession.
The situation is rare enough that it appears in News of the Weird Daily, but still it seems only fair to mention Michael Mohr. After a recent religious conversion Mohr turned himself in for the 2004 murder of Myrna Gonzales. A law enforcement officer commented, "We wish Jesus would solve more of these."