The proposed Anti-Sanctuary Act in New Hampshire requires law enforcement agencies to comply with federal immigration detainers for inmates when safe, while prohibiting state and local entities from enacting sanctuary policies that hinder federal immigration law enforcement. The bill restricts law enforcement from investigating an inmate's citizenship status unless it is related to a violation of state law or authorized by law. It also prohibits blanket policies against compliance with immigration detainers and ensures that government entities cannot limit the sharing of inmate immigration information. Key definitions and penalties for violations are included, and exceptions are made for certain witnesses or victims of crimes to protect their involvement in prosecutions.

The bill is set to take effect on January 1, 2026, and its fiscal impact is indeterminable, depending on the number of enforcement actions that may arise. The Department of Justice anticipates potential costs related to enforcement, which could necessitate additional resources, such as hiring an extra attorney. The Department of Safety warns that the bill may result in longer processing times for individuals under federal detainers, while the Judicial Branch cannot predict its effect on court filings. Overall, local law enforcement may incur increased expenditures to meet the new requirements.