Code of Silence (1985) on Netflix

Eddie Cusack is a tough Chicago policeman facing two crises stemming from a bloodily botched narcotics sting. The first involves a war that ensues between the gang of Tony Luna and Felix Scalese against Columbian "businessman" Luis Comacho, a war that sweeps up Tony Luna's daughter. The second involves Cusack's new partner, Kopalas; during the botched sting Kopalas witnessed another cop, a burned-out alcoholic named Craigie, shoot and kill an innocent youth then plant a gun on the youth, and Kopalas is torn because he fears breaking the code of silence that exists among his fellow Chicago cops - a code of silence that sweeps up Cusack when, at a civilian review board he testifies against Craigie, and is abandoned by his fellow cops when Luna's daughter is kidnapped by Comacho, Cusack is badly beaten by Comacho's gang, and Cusack must settle the gang war (and rescue the girl) once and for all with a "borrowed" robot police tank.