COLUMBIA, S.C. — Former Columbia Police Chief Randy Scott changed his plea from not guilty to guilty in US District Court on a charge of possession of a firearm by an unlawful user of a controlled substance.

The penalty for the federal offense is a maximum term of imprisonment of ten years, a fine of $250,000, and a term of supervised release of at least three years in addition to any term of imprisonment, plus a special assessment of $100. Actual sentencing will happen at a later date.

According to the plea agreement, Scott waives indictment and arraignment and pleads guilty to a "Superseding Information charging, unlawful user of and addicted to a controlled substance."

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The single count reads:

"From an unknown time at least from November 1, 2017, up to and including July 18, 2019, in the District of South Carolina, 

A. The defendant knowingly possessed firearms and ammunition;

B. At the time of the charged acts, the defendant was an unlawful user and addicted to a controlled substance as defined in Title 21, United States Code, Section 802;

C. At the time of the charged act, the defendant knew that he was an unlawful user of and addicted to a controlled substance; and,

D. The firearms and ammunition had been transported in interstate or foreign commerce."

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Under the plea agreement terms, Scott must surrender the nine guns in his possession -- a Mossberg 12-gauge shotgun, Palmetto Armory PA-15 5.56 NATO rifle, a Remington Model 870 Magnum 12-gauge shotgun, two 9mm pistols, a Smith and Wesson .380 caliber pistol, two .22 caliber pistols, and a Glock .40 caliber pistol -- and miscellaneous rounds of .22 caliber ammunition.

Scott worked for the Richland County Sheriff's Department before becoming Columbia Police Chief from 2011 to 2013.

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He resigned the position in 2013, citing post-traumatic stress disorder developed after an officer's line-of-duty death during his time with the Richland County Sheriff's Department.

A statement from US Attorney Sherri Lydon detailed the evidence presented against Scott:

On December 4, 2017, Richland County deputies arrested the driver of a car at the intersection of Old Hopkins and Garners Ferry roads on suspended license, drug and gun charges. The car was later found to be registered to Scott. The driver of the car told investigators from the Bureau of Alcohol, Tobacco and Firearms (ATF) that he and Scott used drugs together and that he had seen Scott with drugs.

On April 2, 2018, Scott was taken to a local hospital for a medical condition. Records indicate that Scott tested positive for cocaine, amphetamine, and opiates and that his diagnosed illness was related to cocaine and methamphetamine abuse.

On July 18, 2018, during the execution of a fugitive arrest warrant at Scott's home, US Marshals found methamphetamine and a large number of guns -- one belonging to the City of Columbia from when Scott was police chief -- in the house. Video from this incident showed Scott pulling a gun out of his waistband and running through the house with the gun, entering a room where it is believed that he disposed of drugs.

On February 25, 2019, J.O., a woman found with Scott in July, was interviewed by ATF agents. She told them that she had met Scott in 2017 and the two did ice and heroin together -- taking ice 1 to 2 times a week for a year.