In 1996 Scott Roeder was arrested after a sheriff's deputy found ammunition and a blasting cap in Roeder's car. His conviction was eventually over turned due to a Constitutional violation. Tim Hrenchir interviewed Roeder's father following that arrest.
If Roeder's father is correct (and as a father he's allowed to see his son through rose colored glasses) then there are more involved in the assassination of Dr. Tiller than just Scott Roeder. “Scott would not kill a fly,” his father said in the interview. “He won’t step on a worm. So how could he possibly, unless he was being used by somebody, be planning anything that would take human life?” (emphasis added)
You have to wonder who really got Roeder to pull the trigger.