Raulie Casteel, 43, of Wixom, Mich., faces 21 charges, including terrorism and assault with intent to murder, in connection with shootings at passing motorists in Livingston County, Mich., over an 11-day period in October 2012.
Casteel also faces 60 similar charges in nearby Oakland County, The Detroit News reported.
Wednesday's determination came in Livingston County's 53rd District Court.
In November, judges in Oakland and Livingston Counties ordered Casteel to undergo separate competency and criminal responsibility tests to determine if he is competent to stand trial, the newspaper said.
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