The New Jersey Laken Riley Act establishes specific procedures for law enforcement regarding the arrest of aliens unlawfully present in the United States who are charged with certain crimes. The bill outlines that if a law enforcement officer determines that an arrested individual is unlawfully present and charged with serious offenses—including any indictable crime, motor vehicle violations involving bodily injury, or crimes defined as aggravated felonies or crimes of violence under federal law—they are presumed to require pretrial detention. This presumption is established notwithstanding the state's Criminal Justice Reform Law. Additionally, the bill mandates that law enforcement officers comply with immigration detainer requests from the United States Department of Homeland Security (DHS) and allows law enforcement agencies to enter into voluntary agreements with federal authorities for immigration enforcement services.

Furthermore, the bill repeals existing laws that prevent state prisons and jails from serving as immigration detention facilities and directs the Attorney General to rescind the Immigrant Trust Directive, which limited cooperation with federal immigration enforcement. The intent of the bill is to align New Jersey's immigration enforcement practices with federal law, particularly the federal Laken Riley Act. The bill also includes provisions for the Attorney General to ensure that any new rules or policies implemented are consistent with the legislative intent of the act and subject to legislative review.