The University of Colorado at Boulder is urging students not to wear Halloween costumes that fuel cultural stereotypes and could be deemed racist or offensive.

"If you are planning to celebrate Halloween by dressing up in a costume, consider the impact your costume decision may have on others in the CU community," Christian Gonzales, CU's dean of students, wrote in a letter. "Making the choice to dress up as someone from another culture, either with the intention of being humorous or without the intention of being disrespectful, can lead to inaccurate and hurtful portrayals of other peoples' cultures."

According to Gonzales, CU students have chosen costumes that "included blackface or sombreros/serapes," overly-sexualized "geishas," "squaws," stereotypical, such as cowboys and Indians, and have hosted "offensively-themed parties," including "ghetto," "white trash/hillbilly" and "sex work."

The parties, she wrote, "reinforce negative representations of cultures as being associated with poverty."

Last year, a Penn State sorority was put on probation after throwing a Mexican-themed party where guests dressed up in sombreros, mustaches and ponchos.

"How any constituent groups or individuals in the University could behave with such insensitivity or unawareness is a question we must both ask and answer," Penn State president Rodney Erikson wrote in an open letter to the Penn State community.

CU is hoping to avoid a similar situation.

"CU-Boulder values freedom of expression and creativity both in and outside of the classroom," Gonzales added. "The CU community also values inclusiveness, respect and sensitivity. While everyone has the freedom to be expressive, we also encourage you to celebrate that you are a part of a vibrant, diverse CU community that strives toward respecting others."

A university CU spokesman told Campus Reform that the school supported the letter.

"When you dress up as a cowboy, and you have your sheriff badge on and a big cowboy hat, that's not a representation of a cowboy,"  Bronson Hilliard, the spokesman, said. "That's kind of a crude stereotype."

CU is not the first school to discourage "offensive" Halloween costumes.

Just last month, officials at the University of Minnesota-Twin Cities distributed a similar letter to students.

"Please keep in mind that certain Halloween costumes inappropriately perpetuate racial, cultural, and gender stereotypes," the letter, signed by the dean of students university’s vice president for equity and diversity read. "Although it may not be the intent, these costumes, and choosing to wear them, can depict identities in ways that are offensive or hurtful to others."

The letter did not specify which costumes it deemed inappropriate. But Mike Schmit, the school's undergraduate student body president, said the message was clear: use common sense.

“As a student, I think you’re better off erring on the side of not dressing like something that can be questionable,” Schmit told the Minnesota Star-Tribune. “Cowboys, for instance — totally fine. Indians — not totally fine.”

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