Both are registered sex offenders, and both are accused of committing crimes that went undetected for a long time, even though red flags were raised.
In Garrido's case, neighbors complained about people possibly living in his backyard, years before his arrest this year for the alleged kidnapping of Jaycee Dugard.
People living in Sowell's Cleveland neighborhood say the awful smell alone should have alerted police that something was wrong long before 11 bodies were found at his home in recent days.
Cleveland city council member Zach Reed tells CNN that he received a call about the stench in 2007 from someone who said it smelled like a "dead body."
He's now calling for an independent investigation into whether police and health authorities should have spotted signs of foul play.
This Saturday at 4 p.m. ET, we're taking a closer look at the Sowell case, and we're raising the question, "Who's keeping watch over sex offenders?"
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