Continuity: At the climax of the film, Macreedy is attempting to use his tie as the 'fuse' for a fire-bomb. Though his 'dead' arm remains stuffed in his jacket pocket, he clearly uses its hand when tearing the tie.
Continuity: Clouds appear and disappear from shot to shot. For example, during the discussion scene on the railroad tracks about 27 minutes into the film, the clouds above the mountains at the tracks' vanishing point appear in wide shots and disappear in tight shots.
Plot holes: When Macreedy tries to escape town with Liz, he doesn't have his suitcase.
Miscellaneous: As the train approaches the town, the horn blows twice, which is the signal for starting up. The mandatory signal for a grade crossing (long, long, short, long) is never blown, although one clearly exists. When the train departs, the conductor makes a confused hand signal to the engineer resembling the horizontal motion that means "stop" rather than the vertical motion that means "go". The engineer never responds with the "long, long" starting signal.
Factual errors: McCreedy rents the U.S. Army quarter-ton truck (jeep) and drives it around with his one arm. That model truck only had a standard transmission. Yet you can hear the gears shift but McCreedy never engages the clutch or works the shifter.
Revealing mistakes: Obvious stunt driver for Spencer Tracy during the chase with Coley.
Errors in geography: Mid-century film, made in the mid 50s and set in the late 40s. The lobby of the hotel, in this desert hamlet, has a slot machine, which the Lee Marvin character is clearly addicted to playing. This would indicate that the fictional desert hamlet is in Nevada, the only state where gambling was legal in those years. The rented jeep, that figures into so much of the action, has California license plates, shown in close-up.