Several English universities have declined to remove diversity requirements from their hiring practices despite the risk of falling foul of new free speech rules, a campaign group has alleged after reviewing job adverts.

The Alumni for Free Speech (AFFS) group said it had identified “very risky” practices across a significant number of institutions in the sector, having studied the recruitment criteria of 162 institutions.

Many of the institutions named by the group have pushed back on the findings, insisting their practices are legal and comply with all regulatory requirements, and the research was based on out-of-date adverts.

The Freedom of Speech (Higher Education) Act, parts of which came into effect on 1 August, makes it clear that universities cannot demand that applicants express or support particular values in order to get a job.

Office for Students guidance on the new rules states that institutions should not require applicants to any academic position to commit, or give evidence of commitment, to a particular viewpoint.