Two-fisted New York police detective Edward G. Robinson is so volatile that he manages to get himself thrown off the force in disgrace. The local gangsters are delighted, in that Robinson had been breathing down their necks. When Robinson goes to crime boss Barton MacLaine insisting that he's through with law enforcement and wants to switch to the other side, MacLaine's chief henchmen Humphrey Bogart doesn't buy the story, but has to go along since he doesn't want to incur the wrath of MacLaine. Robinson offers to show his former enemies how to circumvent the law, making him an invaluable participant in gang activities. Actually, Robinson hasn't gone crooked at all; he's operating undercover, with the full knowledge of the city police inspector, in hopes of locating the "big boys" who've been financing the mob. His diligence costs him his life, but Robinson, with the help of bad-girl-gone-good Joan Blondell, busts the rackets wide open. Former crime reporter Martin Mooney was responsible for the story upon which Bullets or Ballots was based.
~ Hal Erickson, All Movie Guide