LITTLE ROCK, Ark. — Little Rock police on Tuesday dropped a charge against an Arkansas lawmaker who was arrested when officers said he refused to leave a traffic stop he was recording.

Police said they dropped the misdemeanor obstructing governmental operations charge against Democratic state Rep. John Walker, who co-sponsored a law partly aimed at preventing authorities from prohibiting the filming of an arrest. Police Chief Kenton Buckner sent Walker, 79, a letter apologizing for the Monday arrest in downtown Little Rock. Walker did not immediately return messages left at his law office Tuesday.

In his letter, Buckner said he made the decision after reviewing the documentation and video from the arrest and talking with the city’s legal counsel.

“After doing so, I have concluded that you should not have been arrested,” he wrote.

Police said charges would not be dropped against Omavi Kushukuru, an attorney in Walker’s firm who was also arrested at the traffic stop. Buckner also told Walker in the letter that the lawmaker would be reimbursed for the $1,000 bond he posted at the Pulaski County jail following his arrest.

Police spokesman Lt. Steven McClanahan said an internal investigation that was announced earlier Tuesday was ongoing and that no officers had been suspended or terminated. McClanahan declined to elaborate on why the charge against Walker was dropped. A police statement said a review of future training opportunities was also being conducted.

Walker was filming police after they had pulled over a driver for not having a license plate and whom they arrested for having active warrants, a police report released Monday said. When the driver asked why Walker was filming him, he replied: “I’m just making sure they don’t kill you,” the report said. A passenger in the vehicle was arrested for a failure to appear warrant. The report claimed Walker kept talking over officers “in an antagonistic provocative manner” when police tried to speak with him and was arrested after he refused to leave the traffic stop area. The report also said that Walker was overheard later at the jail saying he wanted to file a complaint against only the white officers.

McClanahan said Buckner had ordered the internal investigation and the department had also received complaints about the arrest. McClanahan said police expected to release dashboard camera footage from the incident on Wednesday.

Walker last year co-sponsored the measure that prohibits public officials from preventing someone from recording on public or private property where they were lawfully present unless it presents a risk to someone’s physical safety or constitutes an element of a criminal offense.

Walker has represented his Little Rock district in the state House since 2011 and is unopposed seeking re-election. He has been involved in some of the state’s most high-profile discrimination and civil rights cases in recent years. He has represented a group of families known as the Joshua Intervenors in a desegregation case involving three Little Rock area schools. He also represented Nolan Richardson in the former basketball coach’s unsuccessful federal discrimination lawsuit against the University of Arkansas. Richardson claimed he was fired as retaliation for speaking out about discrimination at the university.

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