SPRINGFIELD — State police forensic scientists could soon get more money to help reduce a persistent backlog of evidence tests for unsolved crimes and pending prosecutions. Legislation introduced by House Speaker Michael J. Madigan would appropriate $6 million to the State Crime Laboratory Fund via monthly deposits from various tax funds. The money — a $1 million increase from 2015 — would be used for high-quality forensic crime labs when the next fiscal year starts July 1. Arlene Hall, commander …