LANSING (WWJ/AP) – The Michigan Supreme Court has denied an appeal from a man who kept a swath of southeastern Michigan on edge for weeks by shooting at two-dozen vehicles along a busy highway corridor.

The state’s high court announced its decision on Wednesday, affirming the 2014 conviction of Raulie Casteel on a combination of terrorism and weapons charges, according to The Livingston Daily Press & Argus. The state’s appeals court last year upheld the conviction by a Livingston County jury.

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Casteel was sentenced in March 2014 to 18 to 40 years in prison, adding to the six-plus-year sentence that stemmed from a related case in Oakland County. His earliest chance for parole is November 2030.

Casteel’s attorney argued his client was troubled but not a terrorist.

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Testifying in his own defense, Casteel said he did it because he believed he was battling demons, and that motorists were part of a government conspiracy against him. During questioning from his lawyer, Casteel conceded that he fired at cars, but that he “absolutely” did not intend to hurt or terrorize any of the drivers.

Casteel told jurors he was filled with fear and anxiety while in traffic, most likely from an undiagnosed delusional disorder. The unemployed geologist, in total, was charged in connection with two-dozen shootings along a 100-mile stretch on and near I-96 through four counties. One person was injured.

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