Being poor, and being impoverished are two different things though. It compounds issues, like morality, absent parents, petty crime, domestic violence, drug and alcohol addiction which in turn create dysfunctional environments in which people learn social rules and morals - we learn from our parents how to be 'moral citizens', and things that interrupt that process create dysfunction in how we learn to live in the world and with others.

Whilst these themes occur outside of poverty, what is important is how they impact child development, and the capacity to 'deal with them' - which if your poor is much harder to mitigate.

"One Nation Under God, has turned into One Nation Under the Influence of One Drug"
[Link]

When does it become a problem then? At what level of 'poverty' does it become ok to steal? Are we allowed to take into account why the thief is in poverty in the first place?

We have now sunk to a depth at which the restatement of the obvious is the first duty of intelligent men. [Orwell]

I understand why some people turn to crime - for example financial reasons, liking drugs etc. But where it gets interesting is why people choose certain types of crime, especially repeat crimes and anti-social crime.

I think poverty impacts that, not causes it, but aggravates the appeal of certain types of crime that isn't 'rational'. Like thugs who just beat people up for fun. Poverty plays a role in making thrill crimes that deal with individual inadequacy fulfilment acceptable outcomes, because it creates alienation, lack of opportunities and achieving means of self worth.

How many people who beat their wives just acting out their own inadequancies on other people. Poverty plays a role in enforcing those inadequancies and failings - because it reinforces the idea of being a failure in people - and their only means of sublimating those feelings, is in deviant behaviour.

"One Nation Under God, has turned into One Nation Under the Influence of One Drug"
[Link]

I've no doubt that all of that is true and yet many people from impoverished backgrounds commit little or no crime.
Morality is not determined by impoverished circumstances but by the individual minds of those concerned. Those minds might well be influenced by the culture that exists inside their environment but they still have free will.

Immigration is a factor in all this because we are allowing people to come here, some of whom are already indoctrinated with a different set of moral standards resulting from a more impoverished environment and it seems, no capacity to know right from wrong.

Not a problem? A rational decision that is understandable? At what point is someone entitled to say they will not obey laws because they perceive themselves to be poor in some degree?

We have now sunk to a depth at which the restatement of the obvious is the first duty of intelligent men. [Orwell]

Often, it's all about perspective. The American Revolution was a violent uprising against what was perceived by the revolutionaries as an oppressive government; which is exactly the same motivation that drove Timothy McVeigh to blow up the Murrah Building in Oklahoma City. The difference being that the majority of the contemporaneous population agreed with the former and not the latter.

We don't do possession; we do defense and attack. Everything else is just wa**ing with a football.