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Jessie McKim has spent the last 20 years behind bars for a murder that never took place.

McKim is serving a life sentence without parole for murdering Wendy Wagnon in 1999. But back in 2013, it was determined that Wagnon actually died from a meth overdose, even though prosecutors have argued that McKim strangled her. However, while the science says that Wagnon was not murdered, a judge has denied McKim's request for relief because he has “not conclusively proved his innocence."

It’s a story that Marshall Project Senior Editor Andrew Cohen has been exploring. Jennifer Bukowsky, an attorney in Columbia, Missouri who has been working on the case for years, joins Cohen to discuss McKim's story.