Yep. This actually happened here in PA last year. A woman was part of a search team for another missing woman. She miraculously discovered the body, as you said, dumped over a hillside in the woods.
And as it turns out her, and the woman that was missing, were lovers, and she had kidnapped her, shot her, dumped her over a hillside, returned to her own mother's house with the gun in her hand and hid the gun. Her mother saw her with the gun that had blood on it and never told police. So many people were outraged that the woman's mother wasn't charged with obstruction of justice at the time, for covering for her daughter's actions.
See the 2nd post down.
http://boards.crimelibrary.com/showthread.php?t=280572
I believe she was sentenced to 30-60 years in prison.