The city is fighting to withhold the suicide note left by a police lieutenant who killed himself after ordering the fatal Tasering of a deranged man, court papers show.

Lt. Michael Pigott left the note before he shot himself in the head just weeks after the incident involving Iman Morales, who fell off a second-story ledge after waving a fluorescent bulb at cops.

Pigott faced a possible trial over Morales’ death, his wife said in an interview last year.

Morales’ mother, Olga Negron, sued the city and Pigott’s estate last year for $10 million in Brooklyn federal court, claiming police violated department guidelines.

Her lawyers have requested a copy of the note as part of the lawsuit. The city argued this week that the records are not relevant to Negron’s case.