MILWAUKEE – U.S. Marshals are searching for a man convicted of lying about his drug use when he purchased a firearm at a sporting goods store in 2021. Investigators say he was using heroin and got into trouble with the law, but is now on the run.

“The original case arises from a two-count indictment,” the U.S. Marshal in the case said.

Gun buyers must complete ATF Form 4473 when purchasing a gun. The document asks about things that could disqualify someone from purchasing a firearm, from felony convictions to drug use. Federal investigators say Brett Christensen, 34, checked a box saying he did not use illegal drugs.

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“When in fact he knew he was an illegal user of heroin, a Schedule I controlled substance,” the marshal said.

Christensen was given time served and placed on supervised release. An order was issued in October 2024 when investigators say he violated that release.

“Just turn yourself in and clear the warrants,” the marshal said.

Christensen is 6′ tall and weighs 184 pounds. It is believed to be in the milwaukee area.

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The U.S. Marshals encourage anyone with information about Christensen to call the U.S. Marshals Tip Line at 414-297-3707. You will remain anonymous.