I suspect that many of the reasons why people are in prison are identical to the reasons why people are attracted to evangelical style religions: poor education, poor critical thinking abilities, poverty, sense of helplessness, sense of being exploited by those with greater economic and educational priviledge, poor health and genetic disadvantage. In other words, it is a mix of innate abilities, environmental deprivation, lack of realistic and perceived opportunities for betterment and oppression by others who have access to what they lack.
A god that is tailor made to care about these people and to reward them for doing something over which they believe they have control is very appealing.
Crime is always worse among the poor and uneducated and so is god belief. Developed countries with the highest levels of social welfare and median educational acheivement (for example, Sweden) have low crime rates and low levels of belief in the supernatural. Developed countries with poor social welfare programs and relatively low median educational achievement (USA) have relatively high crime rates and high levels of belief in supernatural powers.
This relationship is obscured in the US because of the distorted way in which educational achievement is measured in that country, namely, as the "number of years of formal schooling" or "the name of the highest qualification" rather than by internationally bench-marked levels of actual and demonstrable achievement. The U.S. 4-year pre-professional College Bachelor degree, for example, is a very different level than a 4 to 6 year Professional Bachelor degree offered in other English-speaking countries. It is not reasonable to equate these two same-named qualifications when completion or near completion of a U.S. College Bachelor is the minimum requirement for the commencement of a Professional Bachelor program (as it is in Ireland, the U.K., Australia and New Zealand). This explains why Japan does not appear to follow the education-theism rule. [It actually does.]
It is further complicated by the fact that the poor cannot afford good legal counsel and the poorly educated are too stupid to avoid getting caught. In other words, there are probably a lot of poorly educated paupers who should not be in prison and a lot of well-educated rich people who should be.
To add to the complications the US imprisons a disproportionate number of its citizens [5% of the worlds population with 25% of the worlds prisoners.] That is partly due to the incarceration of non violent drug users but also (and perhaps primary) the huge profits that can be sucked up in the private prison system. That lobby rarely supports any prison reform that might reduce the level of incarceration but are generous supporters of more draconian sentencing (ergo more "clients").
All of this fueled by the public's percieved danger level - a level engineered by government, media and individual fear mongers....such as..
Exactly! The US prison population is not a good advertisement for a "christian nation" who claims to be morally and democratically superior to all other nations.
The Californian penal system is nothing short of cruel and unusual punishment for the bulk of the prisoners. The Chronicle did an expose on the state of the prisons several years back. It was very disturbing reading. Overcrowding and lack of medical resources leaves results in prisoners suffering excruciating pain from conditions which would not be tolerated on the outside. Russian prisons look almost tame by comparison.
The reality is that once sentenced, even for minor crimes, the system ensnares the person in such a way that they end up serving virtual life sentences. These may be punctuated with short bursts on the outside where they find that rehabilitation is next to impossible. Once the criminal label has been applied, the person is branded and punished for life. It is a really sick system and a travesty of justice.
The prison systems are a nightmare ruled, in large part, by the prison gangs. This forces the prisoner to ally with a gang for their survival. Once in they have obligations to the gang which may lead to extended incarceration. The obligations often extend after they are released - obligations that may lead to further imprisonment. And round and round it goes.
It's not a system that addresses future crime very effectively, in reality, it fosters future crime.