Magnum on Ice

Plot:

In Part 2 of a crossover story with "Magnum, P.I." (both episodes are shown on the "Murder" DVD, although not consecutively), Magnum has shot it out with a hired gunman at a party, killing him. Magnum claims the thug had fired several shots at him, including one just before Magnum returned fire. But the police can't find the gunman's weapon, and furthermore he was shot in the back. An overzealous police captain calls it murder one (huh?) and throws Magnum into the cooler pending trial. Jessica searches the crime scene and finds a shell casing which doesn't match ...