8 U.S.C. §1252c

Section 1252c originated in the House of Representatives as a floor amendment to the Antiterrorism and Effective Death Penalty Act of 1996 (AEDPA §439).
Section 1252c authorizes the arrest of aliens by state and local officers who have presumably violated §276 of the INA (Reentry of Removed Alien). Section 1252c(a) states in part:
[T]o the extent permitted by relevant State and local law, State and local law enforcement officials are authorized to arrest and detain an individual who—
(1) is an alien illegally present in the United States; and
(2) has previously been convicted of a felony in the United States and deported or left the United States after such conviction, but only after the State or local law enforcement officials obtain appropriate confirmation from the Immigration and Naturalization Service of the status of such individual and only for such period of time as may be required for the Service to take the individual into Federal custody for purposes of deporting or removing the alien from the United States.

The purpose of §1252c was to overcome a perceived federal limitation on the ability of state and local officers to arrest an alien known by them to be dangerous because of past crimes committed in their jurisdiction. The court in United States v. Vasquez-Alvarez, however, found that neither the defendant, the government, or the court could identify any pre-§1252c limitations on the powers of state and local officers to enforce federal law.Section 1252c(b) also mandates cooperation between the AG and the states to assure that information in the control of the AG, including information in the NCIC, that would assist state and local law enforcement officials in carrying out the duties of §1252c is made available to the states.

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