I don't have the time to work this up in the detail required. Believe me, I've spent hours on this and the data is very hard to dig up and even harder to winnow. Many variables.

But I still disagree on your border theory. Illegals are going to move away from the border to their destinations as soon as possible. This will either be agricultural areas, or large cities. That will be where the property and most other crime will happen. Exceptions would be crimes involving the actual border crossings. Crimes per capita as a statistic confuses the issue. A hypothetical county or town with five people in it where one is a criminal would have a number of 20 percent.