Police in Milwaukee, investigating a string of cold-case slayings, have finally identified their prime suspect by obtaining DNA from his toothbrush. Yet Walter E. Ellis sat in prison for three years, and under Wisconsin law he should have been DNA swabbed, and identified, long ago. Nobody knows what went wrong.
the real issue is why the science — taking DNA swabs, and inputting that evidence into a shared database — is so hard for law enforcement to get right, allowing people like the Milwaukee Madmen and Westside
Rapist to evade detection and kill again.