PONTIAC (WWJ/AP) – A man charged in a series of shootings on and off I-96 pleaded no contest but mentally ill to assault and firearms charges.

Raulie Casteel, who made the plea Wednesday in Oakland County Circuit Court, faces up to 12 years in prison when he is sentenced on Jan. 30. Casteel still faces more charges elsewhere related to shootings last October.

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“A key part of this agreement was that he was mentally ill, and that’s what drove him to do this,” said defense attorney Douglas Mullkoff, who has said his client was diagnosed with delusional disorder, a condition associated with maintaining false, persistent beliefs despite evidence to the contrary.

The 44-year-old unemployed geologist is suspected of two-dozen random shootings that took place along a 100-mile I-96 corridor through four counties. Police said they matched Casteel’s gun to bullet fragments recovered from victims’ vehicles.

Casteel had faced 60 charges, including attempted murder, in Oakland County for shootings last fall in Commerce Township and Wixom, the Detroit suburb where he lived. Casteel, who has no criminal history, had been scheduled to stand trial next week.

In a separate but related case, Michigan’s attorney general is prosecuting Casteel on terrorism and other charges in Livingston County.

Mullkoff said he hopes Attorney General Bill Schuette’s office will be interested in reaching a similar agreement.

“We’re hopeful that, with the closure we’ve accomplished here, that they’ll follow suit,” he said.

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Attorney general spokeswoman Joy Yearout said her office is confident in its case and is prepared for trial, which is set to get underway early next year.

“We’ll let the jury decide,” she said.

Assistant prosecutor Jeff Hall said he and Wixom police were able to contact seven of the nine Oakland County victims, and they all agreed with the plea deal.

On professional websites, Casteel described himself as a geologist and soil scientist with experience in environmental cleanup. He is a Michigan native who lived in Taylorsville, Ky., before returning to his home state last year.

After Wednesday’s hearing, his wife, Erin Casteel, said her husband was sick.

“I would just say that Raulie is a good man who got sick, and we’re hopeful that he can now get the help he needs,” she said.

Click here to catch up on this case.

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