Consistently no-platforming people could have a chilling effect on free speech on university campuses and should not take place, according to government guidance.

While student unions are free to choose whether or not to invite individual speakers, placing blanket bans on groups that hold a particular political view is likely to breach English and Welsh free speech laws, according to the guidance released on Saturday.

“Free speech is a value integral to the independence and innovation that embodies the higher education sector in the UK, fuelling academic thought and challenging injustice,” said the universities minister, Chris Skidmore.

The release of the guidance, which was drawn up by the Equality and Human Rights Commission (EHRC), with help from the National Union of Students, the Home Office and a host of other bodies, comes amid a growing debate over free speech on campuses.

While it makes clear that a student union choosing not to invite a speaker because of their views is permissible, it says they should not ban such people from using their facilities altogether. And universities must not allow student complaints to censor course content. Exceptions are made for speech that breaks the law, including stirring up racial or religious hatred.

It reads: “Any decision about speakers and events should seek to promote and protect the right to freedom of expression.”

The guidance makes clear that people have the right to protest against speakers within the law. But it adds: “Protest should not be allowed to shut down debate or infringe the rights of others.”

David Isaac, the EHRC chair, said: “Holding open, challenging debates rather than silencing the views of those we don’t agree with helps to build tolerance and address prejudice and discrimination. Our guidance makes clear that freedom of speech in higher education should be upheld at every opportunity and should only be limited where there are genuine safety concerns or it constitutes unlawful behaviour.”

The guidance adds that “safe spaces”, from which some people are banned in order to ensure that a particular group can express itself without fear, and “trigger warnings”, giving people notice about possibly upsetting subject matter, are not unlawful. It says in some cases the latter can help to promote free speech.

“Safe spaces have been cited as a reason why freedom of expression may be restricted by student unions, although actual examples are hard to find. Creating a ‘safe space’ is not unlawful, but care should be taken when applying any policies in a ‘blanket manner’, for example, across campus, to make sure they do not restrict freedom of expression,” the guidance says.

It adds: “Trigger warnings are used to let people know that subjects are due to come up with content that some of them may find distressing or difficult ... By warning event attendees about the nature of views that may be expressed, trigger warnings may help to facilitate free speech by enabling balanced debate to take place without causing harassment. People who might find the views offensive or distressing can make an informed decision to stay or leave.”

But it cautions that they should not be used in a disproportionate way because that could put people off attending events.