[…] We examine immigrants’ institutionalization rates as a proxy for incarceration, and thus their involvement in criminal activity. […] Immigrants have very low rates of institutionalization compared with the native born. What’s more, immigrants’ relative rates of institutionalization have fallen over the last three decades. More recent cohorts also have better criminal-justice outcomes than earlier cohorts […].
Why is that so? Immigrants self-select, and recent economic conditions and policy made immigration less attractive to troublemaking (potential) immigrants and more attractive to the law-abiding sort (emphasis is mine, via Tyler Cowen).
The analysis is elegant, although I do have some doubts. A (free access) version of the paper is here.