NORTHFIELD — A judge has acquitted a Carleton College student of misdemeanor charges in a crash that killed three classmates and injured another last year.

Judge Colleen King ruled prosecutors failed to prove that 22-year-old William Sparks of Evanston, Illinois, was guilty of careless driving and of failing to drive with due care.

Sparks was driving an SUV that slid into the path of a semi on Highway 3 near Northfield on Feb. 28, 2014.

The crash killed 20-year-old James Adams of St. Paul, 21-year-old Paxton Harvieux of Stillwater and 20-year-old Michael Goodgame of Westport, Connecticut. Another passenger, Conor Eckert of Seattle, was injured. The five students were members of one of the country’s top Ultimate Frisbee teams.

Defense attorney Peter Wold said Sparks is continuing classes at the college.