If you were fleeing by car from a horrible crime, one for which you are likely to get the death penalty if caught, wouldn't you take scrupulous care to observe all traffic laws so you don't get stopped by the police?  Disregard for the law across the board seems to be such a pervasive character trait in some people that they can't, apparently.

Robert Costa, Lindsey Bever, J. Freedom du Lac and Sari Horwitz report in the WaPo, "Charleston Police Chief Greg Mullen said [Dylann] Roof was arrested during a traffic stop in Shelby, N.C., just after 11 a.m., roughly 14 hours after officers responded to the shooting at Emanuel AME."