ALLENDALE, MI - Ottawa County Prosecutor Ronald Frantz claims Grand Valley State University has a policy that discourages prompt reporting of sexual assaults, which undermines authorities' ability to gather evidence and successfully prosecute the crimes.

"We are concerned because it hampers the ability to build cases," Frantz said, referring to the way reports trickle in from GVSU weeks and and sometimes even months after an alleged assault has occurred on campus.

"One of the problems we are having with reports coming so late is that we are unable to gather physical evidence. It is hard to prosecute cases that are not thoroughly investigated.''

When a sex assault occurs on campus, GVSU's police department investigates and is supposed to forward cases with enough evidence to the prosecutor's office.

Over the years, Frantz said he and Sheriff Gary Rosema have had sometimes heated conversations with GVSU officials about the way the school handles these criminal investigations, and how soon the university turns over information to the prosecutor's office to examine for possible charges.

These discussions have included Theresa Rowland, GVSU's Title IX coordinator and equity officer, he said. Under Title IX, discrimination on the basis of gender can include sexual violence such as rape, sexual assault, sexual battery and sexual coercion.

When contacted, Rowland refused to say if she'd ever spoken to Frantz about his concerns.

Mary Eilleen Lyon, associate vice president of GVSU communications, said the school has no policy discouraging prompt reporting of sexual assaults.

"Grand Valley's policy encourages prompt reporting with respect for the victim/survivor's needs," she said, about information reinforced on their Victim's Advocate website and the police department's sexual assault response commitment.

But Frantz insists GVSU's process is "undermining good investigations and prosecutions.'' He said this issue has nothing to do with campus police, rather there needs to be more of a sense urgency about encouraging reporting by those at the GVSU Women's Center and other campus advocates working with victims of assault.

His claims come at a time when the Ottawa County Sheriff''s Department is investigating a string of four off-campus assaults this fall near GVSU's main campus in Allendale.

There have been no arrests in these off-campus crimes, but they have prompted increased police patrols by the college, sheriff's office and private apartment complex security.

Frantz said his concerns with how GVSU has handled its on-campus sex assault allegations have been years in the making.

According to data the college is required by the federal Clery Act to report, there were 15 rapes on GVSU's campus in 2015. The suspects were all known by the victims, the college said. Of the 15, the college sent information on four of those cases to the Ottawa County Prosecutor's for possible prosecution. No criminal charges were filed.

In 2014, there were seven rapes reported on campus, according to Clery data and Grand Valley Police Department records. Two of those cases were sent to the prosecutor's office for prosecution, but no charges were filed, campus police said.

"Neither of the cases (in 2014) could be proven beyond a reasonable doubt and police agreed," Frantz said. He did not recall the circumstances of the four 2015 cases GVSU police sent to his office for possible prosecution.

Frantz said in these types of cases, trace and other evidence should be gathered right away and witnesses need to be promptly identified, otherwise authorities miss their window of opportunity. He said his office currently has one active case involving the sexual assault of a GVSU student.

"A very small percentage of confirmed assaults are reported (to the prosecutor's office)," he said of the sex assaults that have been occurring on GVSU's campus in the last few years.

This year, the Grand Valley Police Department said there have been four on-campus rapes, all reported between Jan. 1 and July 18. These do not include the off-campus sex assaults that made headlines this fall.

GVPD Chief Renee Freeman said in this year's cases, three of the four assailants were known to the victims. She said none of this year's cases have been sent to Frantz's office for prosecution.

While Frantz has not spoken to the media about this before, it's not a new rift between GVSU and Ottawa County authorities.

In fact, Frantz said he's heard things that have made him question if the total number of GVSU assaults in 2014 weren't higher than reported.

He said he was told at a Lakeshore Alliance Against Domestic and Sexual Violence meeting that there had been 40 sexual assaults in 2014 reported by the college's Women's Center, which works with sexual assault victims, among its many resources.

Rowland, GVSU's former victim's advocate, said the university encourages victims to report crimes to law enforcement, connect with the campus victim's advocate, and to seek counseling, as well as working with the Title IX office.

However, when repeatedly asked by MLive and The Grand Rapids Press whether she'd discussed the school's so-called policy with Frantz or Rosema - she refused to say if she's had specific conversations on the issue.

But Frantz said he has spoken to her on more than one occasion about his frustrations with the lack of timely reporting.

Getting the evidence quickly is sometimes the only way to solve a case. Sex assaults in which the victim knows the attacker - the category many on-campus rapes fall into - are the most difficult to prosecute, Frantz said.

"We need that evidence to support one version or the other," he said. "Of those submitted, few are charged, and it has to do with the quality of the case."