Malicious prosecution in New York is established if:
(1) the initiation of a proceeding;
(2) its termination favorably to the plaintiff;
(3) lack of probable cause; and
See the Colon v City of New York, 60 NY2d 78 (1983).
For example, if the police file a false criminal complaint, misrepresented or falsified evidence, withheld evidence, or otherwise acted in bad faith then you may have a claim of malicious prosecution claim against the government.