Fewer than three in 10 accused child molesters are arrested or prosecuted in cities across Maricopa County, according to a review of more than 16,000 cases conducted by CBS 5 Investigates.
The rate is lower than the national average, according to the few studies that have examined the issue.
Law enforcement officials said the low prosecution rate is a reflection of the challenges involved in investigating such sensitive cases. But CBS 5 also found hundreds of cases where detectives failed to follow procedures, and in some cases, failed to do even the most basic detective work.
"There's no excuse for it," said Scott Berkowitz, who is the president of the Rape, Abuse and Incest National Network, or RAINN.
"We know for a fact from all of the academic research that rapists do this over and over and over, and it's kind of obvious why. They get away with it," Berkowitz said.
That appears to have been the case with Hilario Sanchez-Vargas. He is awaiting trial on multiple charges of child sexual abuse, aggravated assault and kidnapping. Police were first alerted to allegations against Sanchez-Vargas in 1999. A police report was filed that year. Another report was filed in 2003. But the accused child rapist remained free until 2012.
It is unclear why police failed to take Sanchez-Vargas off the streets earlier. What is clear is that at least three children said he abused, molested or raped them while he was free.
"I have to tell myself that it wasn't my fault," said one of the victims, whose identity CBS 5 agreed to withhold because she is the victim of a crime.
She said she was 8 or 9 years old when the abuse began. It's been 10 years, but she still bears the emotional scars.
"A year ago, I actually had an attempted suicide," she said.
Her story is far from unusual. CBS 5 Investigates analyzed six years' worth of crime data from seven Valley police agencies. Overall, just 23 percent of the reported child sex crimes cases were forwarded to prosecutors.
"A 23 percent prosecution rate is indefensible," Berkowitz said. "You know, it says that we're just not taking this seriously."
The lowest overall rate came from the Maricopa County Sheriff's Office. Between 2006 and 2011, just 18 percent of the calls resulted in prosecutions. During 2006, the rate was just 12 percent.
The highest overall rate came from the Scottsdale Police Department. They converted 33 percent of the calls into prosecutable cases. Their highest year was 2011, when 51 percent of the cases were forwarded to prosecutors.
"I don't think we'll ever be satisfied until you could say we had 100 percent, or you could say we had no need for our unit because people weren't hurting children," said Detective Brooke Scritchfield, who works in the Scottsdale Police Special Victims Unit.
She and other detectives who spoke to CBS 5 Investigates admitted the challenges they face in investigating these cases are often insurmountable, and even the best units can have low prosecution rates.
"You may have evidence something happened, but you can't necessarily prove it in the court of law. And that is one of the most frustrating parts of our job," said Scritchfield.
"There's no one thing we believe that can solve this issue. It's a systemic issue," said Officer Tracey Breeden, who works for the Glendale Police Department, which had an overall prosecution rate of 19 percent.
Breeden described the barriers detectives in her department face while investigating child sexual abuse cases. They include:
"We don't want to see a perpetrator walk away and continue to do these things. But some of these challenges, we just can't overcome," Breeden said.
The FBI tracks crime statistics, but does not narrow its results to sex crimes against children.
CBS 5 Investigates contacted several of the leading national sexual assault awareness organizations, and found that there are few studies that examined arrest or prosecution rates for child sex crimes on a national level. One study, released in 2000, concluded that just 29 percent of child rape cases are prosecuted.
But CBS 5 Investigates found hundreds of cases where the investigators failed to do basic police work.
The Maricopa County Sheriff's Office came under fire for mishandling more than 400 child rape cases. CBS 5 Investigates discovered that the former chief deputy had diverted resources and detectives away from the Special Victims Unit, while at the same time creating a human smuggling unit. The result was that dozens of cases were left completely uninvestigated for years, until a new chief deputy ordered a complete internal investigation.
The Phoenix Police Department discovered that its child crimes unit detectives were routinely cutting corners and failing to complete investigations. The department is in the process of reviewing and in some cases reinvestigating more than 2,800 child abuse, neglect and sexual abuse cases.
"Just since this review began, we're a child crimes unit that has gone from 27 detectives to 55 full-time detectives. So really, you're talking about an agency that's doubled in size," said Sgt. Trent Crump, of the Phoenix Police Department.
While the Phoenix Police Department and the Maricopa County Sheriff's Office have both doubled the size of their child crimes units, other departments deny that the problem is a matter of resources.
Still, MCSO internal investigation and the Phoenix police review have led to dozens of arrests, including that of Sanchez-Vargas.
"We can't go back on some of these cases and make these victims whole, and we know that," Crump said. "What we're trying to do is make sure that it never happens again."
Advocates like Berkowitz believe the issue needs much more attention from lawmakers and decision makers within police agencies.
"I want them to realize that the system is not working in a lot of places, so let's all get together and figure out how to do it better," Berkowitz said.
At the close of business today, the Maricopa County Attorney's Office provided the following information about the percentage of cases that resulted in prosecution, as relates the number of cases submitted by local law enforcement to the county attorney's office for review.
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