Patrolman James Powers Chicago 1862.

The following was taken from the History of the Chicago Police Department, printed 1915.

James Powers, thought he could handle most anything that came his way.  But in the winter of 1862, he met his waterloo in the shape of "Big Denny" O'Brine, an Iowa tough who visited Chicago for a three week's drunk.
 
O'Brien was "Whooping it up" one day, driving up and down Clark Street, breaking the speed limit.  Powers halted him and was attacked and terribly beaten with his own club.  O'Brien escape.  Months later, when just back on the force Powers was thrown against a curbstone in a fight with a burglar and received internal inuries.  He was granted a furlough and a few week's later dropped dead. 

Authors note.  Driving laws in 1862?  Most large city and most small towns had driving laws.  Mr. O'Brien must have been driving a buggy or wagon.  A one horse buggy or wagon could weigh up to 1200 to 1500 hundred pounds. A one horse buggy at a full run could reach speeds up to 25-30 miles anhour.  That's the same as being hit by a car today.  More people were killed by being hit by a horse than a bullet.