Night Dogs — Kent Anderson

Acclaimed crime writer Kent Anderson's "fiercely authentic and deeply disturbing" police novel, following a Vietnam veteran turned cop on the meanest streets of 1970s Portland, Oregon (Los Angeles Times).
Two kinds of cops find their way to Portland's North Precinct: those who are sent there for punishment, and those who come for the action. Officer Hanson is the second kind, a veteran who survived the war in Vietnam only to decide he wanted to keep fighting at home. Hanson knows war, and in this battle for the Portland streets, he fights not for the law but for his own code of justice.
Yet Hanson can't outrun his memories of another, warmer battleground. A past he thought he'd left behind, that now threatens to overshadow his future. An enemy, this time close to home, is prying into his war record. Pulling down the shields that protect the darkest moments of that fevered time. Until another piece of his past surfaces, and Hanson risks his career, his sanity--even his life--for honor.