There are several tell-tale signs a hotel stay could involve human trafficking.

Payments in cash, frequent short-term traffic to one room and a lack of luggage all point to the potential of a crime that's seemingly erupted in communities around the Twin Cities in recent years.

"Speak Up," a newly-announce campaign in Washington County, partners the county's public health and law enforcement agencies with hotels to help recognize potential victims and how to respond.

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Imran Ali, a major crimes prosecutor who handles most of Washington County's sex trafficking cases, said the initiative aims to "speak up" for those who often won't- or can't- do so for themselves.

"Working with these victims for two years, I can tell you that very few, if any, victims actually come forward- we have to find them," Ali said. "We have to be their voice, and we have to provide the recovery. All of us in this room and all of those in the hospitality industry have the resources and ability to provide them the voice that they need."

The program implements a three-tiered approach to training hotel owners, management and staff.

During the first tier, hotel owners and general managers completed training and provided input to the county. The second tier focused on helping management train hotel staff.

"Frontline staff," who are often the first to witness possible sex trafficking, will complete training by the end of the year as part of the final part.

The program, Ali said, was inspired by discussions between his department and Public Health last year.

Washington County experienced a spike in sex trafficking arrests, from zero in 2015 to 28 since 2016. Authorities reported recovering more than 50 victims during that time.

Lowell Johnson, the county Public Health director, identified sex trafficking as a public health concern with multiple factors, including homelessness, family violence, substance abuse, mental health and sexually transmitted diseases.

"These are social determinants of health and they put us in a place where, when this exists in our community, we are not a healthy community," Johnson said. "A community where sex trafficking is taking place, where men treat women and girls this way, is not a healthy community."

The county doesn't require the training for licensing, but it offers hotels the opportunity to be a part of the solution.

"Our goal has always been to not talk down to hotels, but to engage, empower and enable our hotels to be with us and partner against sex trafficking," Ali said, adding that the majority of Washington County hotels have been eager to participate.

Woodbury Police Chief Lee Vague said his department's cooperative relationship of more than 20 years with local hotels played a key role in identifying crime.

"This is not a hotel problem," he said. "We've got to get past the point of judging which hotel is good and which is bad."

The difference between the two, he said, is a hotel's willingness to work with law enforcement and make employees more aware of the issue.

Law enforcement agencies participating in Speak Up include police departments in Woodbury and Oakdale along with the Washington County Sheriff's Office.

The program, Ali said, launched as part of the county's victim-centered approach to prosecuting sex trafficking cases.

"It's not just the physical, mental or sexual- it's the control, force, fraud, manipulation," he said. "There's so much trauma to these victims, and it's so important that it doesn't just end with an arrest and recovery, it continues on throughout court process."