Northern Border Prosecution Initiative Reimbursement Act - Directs the Attorney General, acting through the Director of the Bureau of Justice Assistance of the Office of Justice Programs, to carry out the Northern Border Prosecution Initiative to provide funds to reimburse eligible northern border states (or local governments thereof) for costs incurred for handling dispositions of criminal cases that are federally initiated but federally declined-referred (i.e., where a decision has been made in a criminal case by a U.S. Attorney or a federal law enforcement agency during a federal investigation to no longer pursue federal criminal charges against a defendant and to refer the investigation to a state or local jurisdiction for possible prosecution). Requires that such program be modeled after the Southwestern Border Prosecution Initiative and serve as a partner program to that initiative to reimburse local jurisdictions for processing federal cases.