LINN — A man who escaped from the Osage County Jail in 2023 after assaulting a detention officer pleaded guilty to nine felonies across five separate cases resolved the same day in Osage County Circuit Court. Court records show prior convictions for felony theft and burglary in 2012 and 2021, respectively.

Alex Michael Stieffermann entered the guilty pleas on Feb. 4 before Circuit Judge Ryan Helfrich. The charges included motor vehicle theft, burglary, property damage, assault of a jailer, and escape from confinement using a dangerous instrument.

Court records show the offenses began in May 2023 and escalated over the following months.

Prior to the Osage County offenses, Stieffermann was arrested in Cole County on Jan. 29, 2023, for second-degree harassment, a misdemeanor. 

The earliest Osage County case dates to May 27, 2023, when Stieffermann stole a motor vehicle.

On June 22, 2023, he committed additional offenses that led to charges of first-degree tampering with a motor vehicle, second-degree burglary, and first-degree property damage. A separate felony charge for damage to jail property followed on June 23.

On Aug. 23, 2023, he pleaded guilty to second-degree harassment in the Cole County case and was sentenced to 90 days in jail, suspended, with two years of supervised probation.

Less than a month later, on Sept. 14, 2023, prosecutors said Stieffermann unlawfully entered the State Tech Vehicle Power Center and stole a 2021 Toyota Corolla.

A probation violation was filed in the Cole County case on Oct. 24, 2023.

Days later, while being held in the Osage County Jail on the pending theft and burglary charges, Stieffermann assaulted a detention officer during a medication round, took the officer’s keys, and moved through secured areas of the jail. Prosecutors said he discharged a fire extinguisher and struck the officer in the head with it, causing injuries that required emergency room treatment.

Stieffermann then escaped from the facility, stripping off his jail-issued clothing and fleeing on foot. A deputy responding to the incident was injured in a vehicle crash. Authorities later located Stieffermann in Linn and returned him to custody.

Stieffermann was previously found mentally unfit to stand trial and ordered committed for evaluation before the cases proceeded.

He ultimately pleaded guilty to all nine felonies, including escape from confinement, a Class A felony, and second-degree assault of a special victim, a Class B felony.

The court imposed prison terms for each charge, ranging from four to 15 years. All sentences were suspended, and Stieffermann was placed on five years of supervised probation. The sentences were ordered to run concurrently, meaning they overlap rather than accumulate additional prison time.

If Stieffermann violates probation, the court could order him to serve the underlying sentences.

Following the February proceedings, a Cole County judge ordered that Stieffermann be reinstated on supervised probation and released from the Cole County Jail with instructions to report immediately to Probation and Parole.