When cops get an important lead in a criminal case, the worst thing they can do is shove it up on a shelf to gather dust.

But that’s what police in south suburban Robbins – and possibly other poor suburbs – have been doing with crime lab results that link suspects to rape cases. As Frank Main reported in Sunday’s Sun-Times, the Illinois State Police crime lab sent Robbins the results of rape-kit tests in 121 sexual assault cases over a number of years, but the police never did anything with them.

No follow-up investigations. No arrests. Nothing, except victims wondering why no one cared.

EDITORIAL

Legislation that would flag police departments that ignore rape-kit test results has been introduced in Springfield, and lawmakers should approve it. It would put a stop to such cases as the rape suspect who remained on the streets for years after being linked through DNA testing to the rape of a mentally disabled 15-year-old girl in Robbins.

That’s a moral outrage.

The bill sponsored by state Sen. Bill Cunningham, D-Chicago, would require State Police to keep track of every case in which rape-kit testing at the crime lab identifies a suspect.

As it works now, any time the state crime lab comes up with a hit, local police are supposed to get a search warrant and obtain a follow-up DNA sample from the suspect and send that to the crime lab, too. But we know that wasn’t happening in Robbins.

The legislation would make it much more likely that the State Police would know when no follow-up DNA samples are being sent to their crime lab, and they could then notify another agency, such as the Cook County sheriff’s office, to take charge. It was the sheriff’s police that was called into Robbins in 2013 and discovered the mishandled rape-kit evidence.

That would be a big improvement over the current system, in which everything grinds to a halt if local police don’t act.

If it seems nutty to you that the State Police crime lab would spend millions of dollars a year to analyze evidence but not make sure local police used that evidence to put away criminals, we’re with you. It is more than nutty.

Nothing could be more unfair to past victims. And nothing could be more to future victims of thugs who should have been locked up long before.

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