car accidents

who do I contact and talk to about the issue of car accidents at the end of my street which is West Wolcott Avenue...Saturday 10/19/13 there was a car accident people drive fast on Matianuck Avenue and I feel that there should be a 4 way stop there.  That was not the only accident that happened there my aunt (my grandmothers sister) was also hit at that intersection and the person who hit her got away with speeding while she got a ticket just because she was turning left off of west wolcott avenue onto Matianuck Avenue