According to Fox News, Jocelynn James, a recovering drug addict, saw on Facebook that former officer Terrell Potter was in need of a kidney transplant.
After coming across a Facebook appeal by Mr Potter's daughter, Ms James reached out to her and offered to donate one of her own kidneys to the cop who had arrested her numerous times.
Jocelynn James, 40, has now been sober for years but once battled drug addiction so severe, she lost her car and job and used break-ins to fund her habit.
She was arrested 16 times between 2007 and 2012, and was on the state's 'Most Wanted' list.
One night, she saw her name flash on the TV as a "wanted" criminal and decided she was "sick of living that life".
The next day, she turned herself over to authorities and stayed in jail for six months. After that she went to rehab for nine months, and today, Jocelynn James is helping other women who are in the same position as she once was.
Police officer Terrell Potter, meanwhile, had been told he faced a seven to eight-year wait for a new kidney when Ms James saw his daughter's Facebook post.
"I still can't tell you what the post says because I never read it fully," she said to VUMC Voice - the news magazine of Vanderbilt University Medical Center.
"I just saw that the man needed a kidney and the Holy Spirit spoke to me and said 'you have that man's kidney.' It was that simple. And I threw my phone down and I was like, 'God, I don't have time to give a man a kidney. I literally work 78 hours a week.'"
According to the Daily Mail, Ms James donated the kidney to Mr Potter in July at Vanderbilt University Hospital in Nashville. They are both doing well.
"That's one of the most unlikely candidates for someone to give you a kidney: somebody you put in jail. And if you asked me for a list of a hundred people who would give me a kidney, her name would not be on that list. Because we had no contact or anything. I just would've never picked her name out. But I'm so thankful that God put her in my life again," said Mr Potter.
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