Grandma's House

A high school in Grand Rapids, Michigan had a Halloween costume party and gave prizes for various costumes. One young man won the prize for the scariest costume, when he arrived dressed as a member of the KKK. After he was awarded the prize, he was suspended from school. That's right. He was suspended for five days. Naturally, the young man, on advice from the school, refused to discuss the matter, saying he didn't want to get into any more trouble. The school is also refusing to discuss the matter publicly. I have a few questions: 1. Were there any regulations stating certain costumes couldn't be worn; and 2. Why was he allowed into the party by school staff members if the costume was inappropriate? Frankly I can't think of a much scarier costume to wear than the one the young man chose. They probably would allow costumes of serial killers, or terrorists, so how are the students to know where to draw the line?