We have a parking issue on our block that the local police department refuses to address.What can we do?

We have a neighbor on our block who is very helpfull when it comes to cleanng up after storms.Here is the issue.The roadway isnt very wide to begin with and also a dead end street.The problem is this,though residents park properly in front of there homes.We have one neighbor who parks several large vehicles cross ways on the street.The city has placed steaks showing where the road way is.And they are clearly blocking half the road.Residents have made several complaints but the police department for what ever the reason,wont correct the problem.We cant see if there are any cars coming down the street before pulling away.This is a safety concern that we cant seem to have addressed.What can we do to fix this?