Six law enforcement officers involved in a narcotics training course refused to be interviewed by state investigators examining allegations that at least one officer gave marijuana to an Occupy protester to see how he would behave.

Records of the now-closed investigation, obtained by the Star Tribune under the Minnesota Data Practices Act, reveal another factor in Hennepin County Attorney Mike Freeman's decision in September not to prosecute officers involved in the State Patrol's Drug Recognition Evaluation program, which trains officers to recognize the symptoms of drug impairment.

The program was suspended after allegations four months ago that some officers provided marijuana to people they found in Minneapolis, including Occupy protesters on Peavey Plaza.

After the Bureau of Criminal Apprehension (BCA) concluded its investigation, Freeman announced in September that there was "insufficient evidence to file criminal charges" because of contradictory statements by witnesses.

But unlike the 2010 investigation of the scandal-plagued Metro Gang Strike Force, in which Freeman blamed officers for keeping silent, he did not make note of it in this case.

Freeman spokesman Chuck Laszewski said the officers' refusal to be interviewed "was only one factor and not necessarily the biggest factor" in the decision on charges.

"This is no different than many of the gang cases we have where the gang members won't testify," he said. "In those type of cases and in this particular case we can only charge and bring a case to a jury where we have sufficient admissible evidence."

Chuck Samuelson, executive director of the American Civil Liberties Union of Minnesota, a persistent critic of police misconduct, defended the right of officers to refuse to talk.

"Police are citizens and entitled to the protection of the Fifth Amendment to avoid self-incrimination, just as anyone accused of [a] crime," he said.

One of the officers who declined to be interviewed, on the advice of his attorney, was Hutchinson police officer Karl Willers, who was accused of dispensing the marijuana. He is currently the subject of an internal investigation by the Hutchinson police department but the details are not public, said Hutchinson Police Chief Daniel Hatten.

While Willers has the right to remain silent in a criminal case, if he declines to speak to investigators in his own department "there could be consequences," Hatten said. He would not say whether Willers has agreed to be interviewed by his office and if so, whether he has denied the allegations.

The remaining five officers were not accused of wrongdoing, according to the BCA documents.

Hutchinson police officer Mark Hanneman also declined to be interviewed, the reports said.

The BCA tried to interview Troy Kemp of the Coon Rapids Police Department. But Kemp's attorney, Fred Bruno, told the BCA that Kemp "respectfully declined to give a statement," a BCA report said.

Dakota County Deputy Bryce Schuenke also refused to grant an interview to the BCA. "He gave a statement to his superiors," his attorney, Larry Rapoport, said Monday. "It was full and complete and that was all he was going to do."

Farmington police officer Pete Zajac also declined to be interviewed, on the advice of his attorney, Paul Engh.

Deborah Ellis, an attorney for Kanabec County Sheriff's Deputy Daniel Lewis, told the BCA he would not talk to the agency, even though he gave a statement to his department, which she said she believed was sufficient.

Several of the attorneys who represented these officers also represented officers who were members of the Metro Gang Strike Force, which was shut down for misconduct in 2009 and was the subject of investigations by the FBI and Hennepin County attorney's office.

The Hennepin County attorney's office charged no one in that case. Freeman said at the time that one reason was that 29 former officers and employees declined to be interviewed.

According to a source familiar with the Strike Force probe, the internal slogan of the Strike Force officers was, "Nobody talks, everybody walks." That was the same slogan of at least some of the officers in the recent investigation of the drug training program, the source said.

Randy Furst • 612-673-4224