Factual error: Hooch is a french mastiff. The dog he gets pregnant is a collie. Different breed dogs do not make purebred puppies. Hooch's pups would be part collie, part mastiff. In the end of the movie, one pup is pure mastiff like hooch and 4 are pure collies like their mother.
Factual error: When the police search of the fish packing plant, a policeman stirs through the lobster tank with a pole looking for evidence. The mistake is the lobsters are all red - live lobsters are deep brownish green - cooked lobsters were put in a lobster tank for the shot. There is no reason to keep cooked lobsters in a tank of water at a fish packing plant.