It was in color and in English. Probably American. I believe I saw it in the early 1980’s on a public television station. It was about a murderer covering his tracks, and it might have been about an actual case. The murderer killed his mail carrier while he was delivering the mail. The murderer realized that if he did not deliver the rest of the victim’s mail, the authorities would be able to figure out quite easily who the murderer was. So the murderer put on the victim’s uniform and went out to deliver the rest of the mail. A voice-over explained the action as it was happening.

Any ideas? Thank you.