Academic freedom at British universities is under threat because of a growing tendency by academics to self-censor, a new report from the Policy Exchange has warned. 

The study, based on the largest poll of UK-based academics in recent years, found that left-leaning academics outnumber those on the right, with the latter facing a "structural discriminatory effect". 

While there is "little support" among most academics for "dismissal campaigns" against colleagues, the minority who would support such a campaign "may exert an outsized effect on the academic climate, restricting freedom". 

"Further, there is widespread support for discrimination on political grounds in publication, hiring and promotion. This threatens academic freedom, and likely results in self-censorship," the report said.

Only 54% of academics said they would feel comfortable sitting next to a known Leave supporter at lunch, while just 37% said they would be comfortable sitting next to someone who held "gender-critical feminist views" on transgender rights.

"It is likely that academics do not discriminate more than other professions, nor does left discriminate more than right," the report reads.

"The evidence, however, is that due to the small number of academics who identify as on the right, there is a structural discriminatory effect against them.

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"Hostile or just uncomfortable attitudes signal to those subject to such discrimination that they should conceal their views and narrow their research questions to conform to prevailing norms, if they wish to progress and enjoy a positive workplace experience.

"Importantly, this demonstrates that the 'chilling effect', whereby dissenting views are not stated publicly, occurs not just due to a fear of feeling uncomfortable. Rather, it is a rational response—particularly for younger academics—to a workplace in which expressing such views may have a negative impact on their careers."

Nearly a third (32%) of all right-leaning academics said they had refrained from airing views in teaching and research, compared to 15% of those in the centre and on the left.

Half of right-leaning academics in the field of social sciences and humanities admitted to self-censoring for " fear of consequences to your career".

Commenting on the findings in The Times, former Chair of the Equality and Human Rights Commission, Trevor Phillips, said that British universities were being "run by a majority who believe they know it all and need to learn nothing". 

"Our university authorities have displayed the spinelessness of a ruling elite in decline, allowing themselves to be bullied by their own students and standing mute while some of their faculty rampage across social media denouncing people (like me) as racists (yes you, Cambridge University) or coon (I'm looking at you, Birmingham City University)," he said.

"What is most disheartening is the widespread fiction that on one side stands an old guard, who allowed women and minorities to be bullied and mistreated, and on the other a brave new movement dedicated to sweeping away oppression.

"The truth is exactly the reverse.

"The fanatics who want to allow men to invade safe spaces for women are the ones creating an atmosphere of fear and exclusion for our sisters and daughters."