By Shaun Boyd

DENVER (CBS4) – The Denver Police Union president will testify before a Congressional committee on Thursday looking into so-called “sanctuary cities.”

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CBS4’s Shaun Boyd interviews Denver Police Union President Nick Rogers. (credit: CBS)

Det. Nick Rogers says he will testify under oath that Denver’s hands-off policy regarding Immigration and Customs makes the city complicit in the heroin epidemic.

“I’ve seen, I’ve lived the whole heroin epidemic in Denver from the beginning,” said Rogers, who has worked for more than three decades in narcotics.

Until last October, he says, he worked closely with federal immigration agents to deport some of the most dangerous drug dealers.

“Now they’re being released from jail within 32-48 hours, and they’re back selling heroin again,” he said.

(credit: CBS)

He blames a city ordinance that he says bars him from communicating with ICE, fueling, he says, the heroin epidemic.

“They’re protecting the criminal element. They’re out there running with impunity. They’re not even looking over their shoulders.”

Deputy Chief Matt Murray disputes that.

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“He clearly doesn’t understand the training or ordinance,” Murray said. He says Rogers can contact ICE.

CBS4’s Shaun Boyd interviews Denver Police Deputy Chief Matt Murray. (credit: CBS)

“To get info to help him prosecute criminal activity. That he can do. What he can’t do is assist the federal government in enforcing civil federal statutes,” Murray said.

Congressman Ken Buck notes many immigration violations are criminal, but DPD can’t ask ICE or any suspect about their immigration status.

The city says ICE receives fingerprints on everyone arrested, but that only flags those already in the system. ICE is not allowed in the jail to interview suspects.

(credit: CBS)

Buck – who invited Rogers to testify before Congress – says the city is tying its officers’ hands.

“In so doing, they give aid and comfort to those who have broken our laws and continue to break our laws and make our community unsafe,” Buck said.

“They’re playing politics, and they’re playing politics with the safety of the citizens and I think that’s wrong,” said Rogers.

Buck says the congressional hearing is meant to help Congress as it develops comprehensive immigration reform.

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Shaun Boyd is CBS4’s political specialist. She’s a veteran reporter with more than 25 years of experience. Follow her on Twitter @cbs4shaun.