News organizations have long chronicled problems with investigating reports of rape. Backlogs in rape kits. Cynical efforts to bury rape cases to make a police department's crime fighting statistics look better. Failures to fully exploit the powerful investigative tool of DNA.

"An Unbelievable Story of Rape," a joint reporting effort by The Marshall Project and ProPublica, reinforced some of the most basic ways police could improve their handling of rape cases. These steps offer the promise of both catching the guilty and protecting the victimized.

1. Check with police agencies where the suspect previously lived or traveled. Our reporting showed the value of this simple step. Police investigating a series of rape allegations against former NFL star Darren Sharper never contacted the authorities where he had previously lived. They were all working in isolation — allowing Sharper to rape or attack nine women in multiple states over three years.

In " An Unbelievable Story of Rape," the police in Colorado reached out immediately to their fellow agencies. And within six weeks, they had nabbed Marc O'Leary, a serial rapist now serving 327½ years in prison.

2. Use the FBI's Violent Criminal Apprehension Program (ViCAP). ViCAP is an FBI database designed to catch serial killers and rapists based on the similarity of their behavior. Using data provided by local law enforcement agencies, ViCAP searches through unsolved crimes to seek out similar patterns — say a certain knife that was used in several attacks. Then it suggests a possible match.

ViCAP may be especially useful in rape cases. First, a large number of rapists are serial offenders. One-third to two-thirds of rapists commit multiple crimes, according to studies. In contrast, only about one percent of murderers are serial killers. Also, only about half of all rape cases involve DNA. ViCAP is built to catch serial rapists who don't leave DNA. In Canada, a similar system is credited with linking together 7,000 crimes since 1995.

But in the U.S., local police don't feed much information into ViCAP. And with a paucity of information, the system rarely turns up good matches.

3. Be aware of myths regarding rape. Criminal experts talk about a hypothetical person called the "righteous victim" who was attacked during a "real rape." That's a woman with no blemishes in her past who is raped by a stranger, tries to fight him off and then promptly reports the crime to police. That victim and that crime exist. But they are not common.

The truth is, rape is a crime with all kinds of victims who respond in all kinds of ways. Women often don't go to the police right away. And they can be pastors or prostitutes. The vast majority know their attacker. Only 13 percent of rapes are committed by strangers.

Any police officer who may be involved in a rape investigation would do well to read the evidence-based findings — many of them surprising — about what rape looks like. Useful resources include the International Association of Chiefs of Police and End Violence Against Women International, a non-profit organization that trains police officers in how to conduct rape investigations. Last week, the Department of Justice released its own guidelines.

4. Listen. This is the most obvious, perhaps. Cops, like journalists and prosecutors, can have an innate skepticism about the people they encounter in their line of work. That makes some sense, for there are no shortages of liars and criminals. But it's important to simply listen to a victim's story, and then to check it out. It takes courage for a woman or a man to come forward and tell the police they were raped. Cops can respect that bravery by not allowing the small minority of people who are fabulists to poison their objectivity or diligence.

Before charging someone with a false claim of rape, be very sure that you have the evidence to make a case. There is a good reason for contemplating the prosecution of people who falsely report rape. Innocent people can be harmed. Reputations can be ruined. Precious police resources can be wasted. But police experts say the cost of routinely filing such charges can also be high. Women who fear they might be prosecuted if their reports of rape are not deemed believable may be scared off from reporting at all. Only about one-third of rapes are even reported to police — due in part to the long judicial history of dismissing women's accusations. The bottom line in dealing with suspicions of false reporting is to take the charge like any other. You have to prove that the person invented the story beyond probable cause. That means collecting evidence, witness statements and all the rest before filing such a charge.

For crisis support: Contact the National Sexual Assault Hotline (800-656-HOPE).

Related coverage: For more coverage, read ProPublica's previous reporting on an "unbelievable" story of rape, how flawed rape statistics hamper rape prevention, and the police failure to stop a former NFL star's rape spree.