It is estimated that as of FY 2009 the total alien -- non-U.S.-citizen -- population was about 25.3 million, incl. about 10.8 million aliens without lawful immigration status. Some aliens have been convicted and incarcerated (criminal aliens). The fed. gov¿t. bears these incarceration costs for federal prisons and reimburses states and localities for portions of their costs. This report addresses: (1) the number and nationalities of incarcerated criminal aliens; (2) the types of offenses for which criminal aliens were arrested and convicted; and (3) the costs associated with incarcerating criminal aliens and the extent to which the Dept. of Justice's methodology for reimbursing states and localities for incarcerating criminal aliens is current. A print on demand report.