We have to concede that even criminals have values albeit their own. Values or morals, what is viewed as right and wrong are within everyone even criminals.
Many criminology theories look at the differences between those who commit crime and those who don't. The neutralization theory proposed in the late 1950's by Sykes and Matza (2001) suggests that rather than having values differing from societal values offenders have their own values that coexist with societal values. This theory is quite in depth but one worth looking at when questioning values linked to crime. As experience showed me, criminals do have values and are people not that unlike everyone else save a handful who were just plain evil.
A lot of those I arrested wanted to know why I wasn't arresting the "real" criminals. The thief wanted me to go after drunk drivers. The drunk drivers wanted me to go after the drug dealers. The drug dealers wanted the rapists caught. Rapists rationalized that child molesters deserved more law enforcement attention. Child molesters wanted the unsolved murders solved. All saw someone doing worse than themselves yet all expressed concern for the safety of society through their displaced reflections. Only a handful did not have values surrounding their own personal welfare and the welfare of others.
Most have the knowledge or value of what was ultimately right and wrong. Which is why confessions are easier than most think. Society may wonder about the legitimacy of confessions obtained by police, but criminals normally want to own up to their actions and not carry around the weight of doing the crime once confronted with being caught. It's like catching a child with their hand in the cookie jar who initially denies being caught (even with the hand in the cookie jar). How that child is confronted often determines accepting responsibility or continual denial. Everyone has the value of self protection along with some inner value of what is good and right.
Numerous confessions are obtained by pulling out those inner values and showing the person all hope is not lost. The vast majority of criminals are not the evil few that society has to contend with and once this is pointed out to them, combined with the fact that many people commit crimes they realize they are not as bad as they think. This eases the burden they carry and it's not so hard to admit what they did.
Almost everyone agreed that they would not like it if someone did the same thing to them. Why else would drug dealers report to the police that someone stole their drugs? The values of those who commit crime may apply to a smaller segment of society, may be skewed and may not conform to what others think, but they do have values.
Sykes and Martza opened the door for looking at values of criminals related to crime and others have expanded their research. It is worth looking at without bias or prejudice.
Curran, Daniel J. and Renzetti, Claire M. Theories of Crime. 2nd Edition. 2001. Pearson Education Co. Needham Heights, MA.