The United States Constitution bars Congress from "abridging" freedom of speech.

　　But at a U.S. Senate Judiciary Committee hearing this week, some speakers said free speech is not being protected enough at American colleges.

　　Zachary Wood is a student at Williams College in Massachusetts. Wood heads a group called "Uncomfortable Learning." The group's aim, he told the committee, is to invite speakers whose opinions are unpopular and troubling to college students.

　　Two years ago, Wood, who is African American, invited a speaker who had written about the results of blacks on intelligence tests. Some people described the speaker's writings as racist.

　　Wood said the school's president canceled the speech, and he says that was wrong. Students, he said, should have a right to hear the speaker, and express objections to the speaker's comments directly to him.

　　Texas Senator Ted Cruz is a member of the Judiciary committee and the Republican Party.

　　Cruz said even morally indefensible comments, such as expressed by hate groups like the Ku Klux Klan and Nazi Party, should be a permitted.

　　The solution to hateful speech, he said, is not stopping it, but "confronting it with truth."

　　Hearing follows incidents blocking speeches

　　The Judiciary Committee hearing was called after a series of cancelled or blocked speeches at American colleges and universities.

　　Political scientist Charles Murray has written about connections between intelligence and race. He was invited to speak in March at Middlebury College in Vermont.

　　Some Middlebury students spoke up during Murray's speech and shouted him down. After the event, protesters, some wearing masks, pushed the speaker and the professor who questioned him. Last month, the university punished 74 students it said interfered with the speech.

　　Cancelled speeches where free speech movement started

　　British media personality Milo Yiannopoulos was asked to speak in February at the University of California (UC), Berkeley. But university officials cancelled the speech after violent protests.

　　In April, the school denied permission for a speech by another conservative, Ann Coulter, saying it should take place at another date when it could provide better security.

　　But after legal action was threatened, university officials agreed the speech could move forward. Coulter decided not to give the speech because of the threats.

　　UC Berkeley is where the free speech movement on American college campuses began in the 1960s.

　　At some schools, safe areas were set up where students can go – places where they will not hear speech they might consider threatening.

　　Iowa Senator Chuck Grassley, a Republican, chairs the Senate Judiciary Committee. He objects to limits on free speech.

　　"When universities suppress speech, they not only damage freedom today, they establish and push norms harmful to democracy going forward," Grassley said.

　　But Senator Dianne Feinstein said sometimes schools have no choice but to block speeches when faced with violence, often by people who are not students. Feinstein is the committee's top Democrat.

　　Fanta Aw is acting vice president of campus life at The American University in Washington, DC. She said her university supports public discussion, "no matter how controversial."

　　But there are limits, she said.

　　"As an institution, we draw the line when expression has the potential to incite violence and/or is a direct threat to members of our community."

　　On the final day of the spring term, someone hung bananas from nooses on the American University campus grounds. It happened the same day a black woman became student government president.

　　‘Only one point of view'

　　Zachary Wood, the Williams College student, said he is a liberal Democrat. But he said it isn't a good thing when students only hear a single liberal opinion on many issues.

　　Williams College President Adam Falk said his college "appreciates Zach Wood's work as a champion of campus free speech."

　　The college president told VOA that he and Wood "share a commitment to free expression of ideas on campus."

　　I'm Bruce Alpert.

　　And I'm Anna Mateo.

　　Bruce Alpert reported on this story for VOA Learning English. George Grow was the editor.

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