SPRINGFIELD — Police in Massachusetts have shot a man they say led them on a low-speed car chase before putting his vehicle in reverse and backing toward officers.A spokesman for Springfield police say the suspect refused to pull over for a routine traffic stop at about 10:30 p.m. Tuesday.The chase ended when the driver struck a parked vehicle, a porch and fence.Two officers got out of their cruiser and were approaching the vehicle when it backed up.