There can be all kinds of reasons why students might oppose a specific person being allowed to speak at their university. It’s not easy to determine why they want what they want. | Photo: istockphoto

In 2020, a study by Matthias Revers and Richard Traunmüller – a sociologist at the University of Leeds and a political scientist at the University of Mannheim, respectively – found that students were keen to banish unwelcome opinions from their campus. In an interview with Horizons at the time, Revers added that: “Up to a third of students also wanted to remove undesirable books from the library. That’s shocking”.

But the sociologist Claudia Diehl and the political scientist Nils Weidmann, both from the University of Constance, criticised the conclusions reached by the study. For example, if a speaker were disinvited because they argued that there are only two biologically determined genders, this could be interpreted either as discrimination against their stance, or as an act of protection for transgender people.

Normally, researchers would now conduct a counter-study. But instead, Traunmüller and Diehl opted to engage in a so-called adversarial collaboration to design a new study that could distinguish between their respective hypotheses.

In order to examine the attitudes behind the responses they collected, more than 3,300 students at German universities were presented with fictitious events representing conservative or progressive positions that either presented a single point of view or demanded specific action. The participants then had to decide whether the university authorities ought to cancel the event in question.

In November 2025, Diehl and Traunmüller published a joint commentary on the student responses in the weekly newspaper Die Zeit: “The result was clear: if the conservative variant of a specific stance is presented, students’ willingness to restrict academic freedom increases significantly”. The political content proved more controversial among the students than the possible concrete consequences for a marginalised group. The two researchers have now called on universities to assess moral reflexes in future, and to ask themselves: “What harm would be done if we allowed a voice to be heard?”