CHICAGO (CBS) — Newly released police body camera video shows Illinois State Rep. Kambium Buckner (D-Chicago) undergoing field sobriety tests the night he was arrested for driving under the influence in Springfield in March.

According to a police report from the Sangamon County Sheriff’s office, Buckner was arrested shortly before 3 a.m. on March 29 near the Illinois State Capitol, after police found him asleep in his vehicle, stopped through several cycles of a traffic light.

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Police said Buckner’s breath smelled like alcohol, and he failed field sobriety tests and refused a blood alcohol test at the scene.

Body camera video obtained by the Illinois News Network shows Buckner telling police he is a state representative, and was just exhausted after four days of legislative session in Springfield. He admitted having one drink at a local bar that night, and said a plastic cup in his car belonged to someone else who had been in his car.

“It’s just ice,” Buckner said. “It wasn’t a full drink.”

The video also shows officers conducting field sobriety tests, including having Buckner follow an officer’s finger with his eyes without moving his head, stand on one foot, and walk in a straight line. Police noted Buckner swayed back and forth while standing on one leg, and couldn’t keep his balance or walk heel-to-toe while walking a straight line as instructed.

“His movements were slow and he struggled to form sentences on occasion. He agreed to perform SFSTs [Standardized Field Sobriety Testing]. During HGN [Horizontal Gaze Nystagmus] he showed all six signs of impairment. During the walk and turn and one leg stand he showed signs of impairment. He refused to provide a breath sample in the PBT [Preliminary Breath Test] or the jail,” police stated in their report.

While taking the tests, Buckner told police he has glaucoma, a torn Achilles tendon and torn meniscus in his left leg. When asked to take a breathalyzer test, he refused, saying he wanted to go back to his hotel to go to sleep.

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“I’m really just trying to go back to the hotel and go to sleep and go back to session in the morning and be done and go back to Chicago,” Buckner said. “I’m an attorney. I don’t want to put myself in a position I shouldn’t be in.”

Illinois State Rep. Kambium Buckner was arrested for DUI in Springfield on March 29, 2019. (Source: Sangamon County Sheriff)

Before taking Buckner into custody, an officer tried to explain that a Breathalyzer test might show Buckner was not drunk.

“At this point, I believe you’re over the legal limit to drive. What this will do is either verify that or disprove it. Now, if you’re saying you’re sleepy, you only had one or two drinks, a guy your size, if you only had one or two, there’s no way you’re going to be above the legal limit,” the officer said. “I think you may have had more than one or two, and I think you’re going to be above it.”

Buckner was charged with driving under the influence and driving below the minimum speed limit.

He later was released on bond, and has pleaded not guilty. He has not responded to requests for comment about his arrest.

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Buckner was appointed in January to fill the 26th District seat vacated by Christian Mitchell, who resigned to be a deputy governor for Gov. JB Pritzker.