Case was about the murder of a young woman in, or around, St.Joseph, Missouri. She was being stalked prior to her death. A letter was later found by a young boy at a shopping mall that provided a clue to her death. It was on one of the late 80's episodes. Thanks,

That was Mikki Jo West (http://www.sitcomsonline.com/boards/showthread.php?t=132950&highlight=mall).

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