I guess they are all dumb or they would have picked a better line of work.
Here's a guy who tried to show his love for his latest girlfriend, but it all went up in flames. http://www.truecrimereport.com/2010/12/leonard_spagnolo_stupid_boyfri.php#more
Here are the 21 dumbest criminals. My fave being the author. And no I've never truly committed any crimes I've written about.
A top ten list of dumb criminals. My favorite is the winner.
I could probably go on for days, but I'll leave you with this one.