Wisconsin lawmakers took a break from their fierce fight over union bargaining rights in 2011 to craft a law with bipartisan support: They ordered police to swiftly submit rape kits for DNA tests if the evidence could help identify a suspect.

Republicans and Democrats were alarmed by reports that investigators in other states had ignored such rape kits — which contain skin, saliva and other samples collected from assault victims.

"We don’t want (untested kits) sitting at the police station or office forever," former state Rep. Tamara Grigsby, D-Milwaukee, said at the time. "It’s a public safety measure."

But a USA TODAY NETWORK-Wisconsin investigation has found that for years after that law took effect in 2011, police agencies all over the state shelved hundreds of untested rape kits with no known suspect. The law didn't require police to send in DNA samples when they already had a suspect, because legislators were most concerned about rapists who were unknown and on the loose.

Testing rape kits can help investigators find or exonerate suspects by matching DNA with national offender databases. It can also help link together cases from different places, revealing serial offenders.

A state Department of Justice spokesman estimated last year that a "small number" of untested kits since 2011 have involved unknown suspects. On Wednesday, after USA TODAY NETWORK-Wisconsin questioned the accuracy of that estimate, the department said about 400 untested kits since 2011 have involved unknown suspects.

By then, the news organization had obtained public records revealing:

► Milwaukee police collected and left untested 200 kits involving unknown suspects after lawmakers approved the 2011 mandate.

► Madison police didn't send 83 such kits to state labs for testing after the law.

► In northeastern Wisconsin, police in Appleton, Green Bay and Fond du Lac each collected and left untested eight kits involving unknown suspects. The Fox Crossing Police Department shelved one kit.

► Police in Stevens Point, Janesville and Kenosha each shelved a handful of kits, and the Waukesha County Sheriff's Department left one in storage for about two years before shipping it to state labs. The victim in that case was a 17-year-old girl.

Department of Justice spokesman Johnny Koremenos pledged Wednesday that every post-2011 kit with an unknown suspect will be tested as part of an ongoing effort to analyze thousands of old rape kits from across the state. He also said state officials are working with police to ensure evidence is submitted to crime labs as required.

USA TODAY NETWORK-Wisconsin contacted police agencies that didn't send in kits after 2011, and officials either brushed aside questions about the evidence or said they believed they had complied with state law. Only Green Bay police said their kits should've been tested. Some agencies said it had been unclear until recently which kits must be sent to crime labs under the mandate.

Vic Wahl, an assistant police chief in Madison, said the new law didn't clearly define a sexual assault case and what step should trigger testing.

"If the DA’s office declined to prosecute a case I think there arguably has not been a sexual assault," Wahl said. "Or if a victim is tested but then declines to cooperate (or) provide a statement, the same could be true. This lack of clarity was shared by police agencies across the state."

Koremenos said the state is working on a "legislative overhaul" of how rape kits are handled to better account for the wishes of survivors, but didn't elaborate. The agency has received millions in federal grants since 2015 to study and test rape kits and improve Wisconsin's response to sexual assault.

"It has become clear, as a result of this project, that we need significant reform of our laws to ensure that this initiative is not necessary again," Koremenos said.

Green Bay police Lt. Jeff Brester said his agency’s eight rape kits with unknown suspects “technically by law we should’ve sent them in." He also said it remains unclear when officers are supposed to send kits for testing, so his department now sends all kits. He said officers need more guidance from the state.

"I don’t know what the heck to do," Brester said.

Last-minute law

Wisconsin's first and only rape-kits-testing law came as a surprise to advocates for sexual assault survivors as well as law enforcement officials.

Democratic legislators proposed the mandate during the final stages of the state's budget-writing process in 2011. The idea had received no public hearing or input from crime lab officials, and initially drew concerns about cost.

But two influential Republicans — Sen. Alberta Darling and Rep. Robin Vos — both backed the mandate and it landed in the final state budget. Vos, who now holds the state Assembly's top post, called it a "reasonable idea."

Grigsby first urged the mandate by describing shelved rape kits in Illinois that led police to track down suspects after DNA tests. She raised concerns that Wisconsin might be ignoring evidence and missing offenders, too.

The scope of untested rape kits in Wisconsin was unknown at the time. It would take a state-led team of sexual assault experts about three years to discover more than 6,000 kits were sitting in police and hospital storage rooms.

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Earlier this month, Attorney General Brad Schimel's Department of Justice released an update that found that in 33 cases so far, kits have helped authorities pinpoint suspects who were previously unknown to investigators.

State authorities have not said if any of the 33 cases involve rape kits collected after state testing became mandatory. The details of only two cases are known because prosecutors have filed charges: an Eau Claire man is accused of sexually assaulting a Menasha woman in 2008, and a Marion man was charged just this week with assaulting a 17-year-old girl nearly six years ago.

Debate over victim choice

Among the hundreds of rape kits involving unknown offenders that USA TODAY NETWORK-Wisconsin found, police records and interviews suggest many were shelved years ago as a result of victim decisions.

Often police records describe the kits as involving victims who were uncooperative or declined to pursue charges. Appleton Police Sgt. Dave Lund said his agency's eight kits came from hospitals with no patient information.

"Without a complainant (or) victim to interview, we are unable to determine whether the kit meets the requirement (to submit)," Lund said.

Milwaukee police spokeswoman Sgt. Sheronda Grant said most of that agency's 200 untested kits also came from hospitals, and victims didn't wish to report a crime. The kits were stored in case victims later wanted to file a report.

"There were no guidelines in place regarding how hospitals should handle rape kits for victims who did not wish to report to law enforcement," she said.

However, the single-sentence mandate lawmakers wrote in 2011 does not contain any exemption based on victim choices.

The law requires sending kits "whenever a Wisconsin law enforcement agency collects, in a case of alleged or suspected sexual assault, evidence upon which (DNA) analysis can be performed, and the person who committed the alleged or suspected sexual assault has not been identified."

Looking at the language, state Department of Justice authorities have adopted the position in recent years that allpost-2011 rape kits collected by police and involving unknown suspects must be tested under state law — whether or not victims consent.

With the Waukesha County rape kit involving the 17-year-old victim, police records show the girl and her mother were adamant in 2014 that they didn't want to pursue charges. The girl agreed to provide a statement saying she was sexually assaulted, but she refused to provide details or file a crime report.

When the Waukesha County Sheriff's Department collected her rape kit, the situation appeared to meet the state's testing mandate: A person had alleged a sexual assault and authorities had no known culprit.

Sheriff's Capt. Patrick Esser said the 17-year-old's rape kit was submitted in a timely manner — echoing language in state law — even though he acknowledged the evidence remained in storage until state Department of Justice officials requested it two years later in December 2016.

"That was not an oversight," Esser said. "I can't discuss details of the case."

Attorney general's pledge

Ian Henderson of the Wisconsin Coalition Against Sexual Assault said his organization supports the rape-kits-testing mandate from 2011, but the law made it difficult for advocates to communicate with survivors about their rights during a public awareness campaign that launched last year.

"We couldn’t really say, 'No kit will be tested without your consent' because if a kit fell into this (law) and was post-2011 and it was an unidentified suspect, the law says that has to be tested," he said. "We don’t want to make a promise to a survivor that we can’t keep."

To further complicate matters, Wisconsin's attorney general, Schimel, has recently and publicly pledged to victims that no old rape kits will be tested without their consent.

"We should never, never go forward and test things taken from a person’s body without their consent — unless we get a warrant from a judge telling us to do it because they committed a crime," Schimel said during a budget hearing last year.

Behind the scenes, Department of Justice officials have moved to create a system for handling rape kits that fulfills Schimel's pledge. Hospitals are no longer supposed to send kits to police when survivors don't want to pursue charges. These kits are now sent directly to state facilities for up to 10 years in storage.

Henderson said his organization would support incorporating the state's new system for handling rape kits into state law.

Lawmakers suggest changes

Last year, state Rep. Melissa Sargent proposed expanding the 2011 mandate so police agencies would be required to submit all rape kits to crime labs for testing or storage within 30 days of collection. The idea never gained traction.

"We need to make sure that these (kits) are being tested and being tested in a timely manner," the Madison Democrat said in February, when it became clear Republicans wouldn't take up the proposal this year. "Folks deserve closure. They deserve to be able to get on with their lives."

GOP lawmakers have been satisfied leaving rape kits policy to Schimel, a fellow Republican who in his role as attorney general controls the state crime labs and works with local police agencies to guide submission practices.

Schimel is campaigning for re-election this year and has touted himself as a champion for testing rape kits. He is being challenged by Democrat Josh Kaul, a Madison lawyer and former federal prosecutor, who has made a campaign theme out of what he believes is Schimel's slow testing of old rape kits.

Darling and Vos, the two Republicans who backed Wisconsin's 2011 mandate, did not return messages seeking comment. Grigsby, the Democrat who first urged the mandate and defended it under GOP questioning, died two years ago after battling cancer.

Jennifer Shilling, who joined Grigsby in proposing the mandate and now holds the Democrats' top seat in the state Senate, said she supported modifying state law to clarify any confusion among law enforcement about its requirements.

"If there is some vague language or it's too broad, then we certainly need to make a correction," she said. "We need to make sure that the testing of these rape kits is a priority."

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