SIOUX FALLS, S.D. (AP) — A South Dakota student accused of sexual assault is suing the school that suspended him, a case that highlights the differences in how university and criminal investigations of such reports are carried out.

Koh Evan Tsuruta's lawsuit says Augustana University should wait on its investigation that will determine if he is expelled until his criminal case is resolved. He has denied the allegations through his attorney.

Tsuruta's attorney says Augustana's investigation denies him his constitutional rights and presumes guilt instead of innocence.

A spokeswoman for the American Association of University Women says the school's goal is to maintain a safe campus, as federal law requires it to.

The organization Boys and Men in Education says of about 90 similar lawsuits since 1992, very few students have prevailed.

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