A specific crime can be rational for one person and not for another.
Assuming you have people who are thinking clear (not on crack or what not), and not committing a crime out of the excitement (think vandalism) it can depend on life circumstance on whether or not a particular crime is rational. Imagine I accurately know the chance of getting caught for stealing a car and I can get $500 for it at a chop shop. If I need to pay rent or pay for food or heat for my family I am more likely to steal the car than if I just wanted a new pair of shoes and a jacket. The down side is the same, going to jail, paying a fine, stigma in society but the upshot is much higher if I succeed, providing for my family, being warm and safe from environment.
It is not alway irrational to commit a crime (assuming we have a goal of our own or those we care about wellbeing and not those impacted). What determines the rationality is the chance of getting caught and what happens if we do not commit the crime.
We traditionally think that getting more of what we want is how we get more things of value. But we can also change what we value.
Value is a relationship between the thing of value and the thing that experiences it.
1. If we change the number of things we have that we find valuable we will have more or less of what is valuable to us.
2. If we change what we find valuable we will have more or less of what is valuable to us.
These are two complete different ways of looking at gaining or losing valuable things and we often only look at the first when talking about having more or less things of value.
This is one of the main points in stoic philosphy.
It is also very useful in thinking about economics. If wealth is having more of what we value changing what we value is as useful as getting more of what we currently value.
One of the main issues in talking about ethics is that people are referring to different aspects. Ethics can be talked about in a number of ways.
Some people separate ethics into:
Meta: what it means when people talk about right and wrong
Normative: what is actually right and wrong, or how should we decide
Descriptive: what do people think is right and wrong
Applied: what actions should we take to do what is right
These are all very interesting but different concepts. One person may be talking about normative and someone else may be talking about descriptive. This can cause a lot of disagreement and confusion. (this problem also happens in a lot of other areas of disagreement between people)
This is not to say people do not have real disagreements on the topic. It is just that many of the disagreements have to do with what aspects of ethics people are referring to.