How do you protect and police freedom of speech on campus and in society?

Arif Ahmed is a Cambridge Philosopher who is now responsible for enforcing new freedom of speech rules on universities, colleges and students.

He took office at a time when there is particular focus on a vexed question: where the boundary should lie between free speech - which should be protected - and speech that threatens, intimidates and leaves people feeling unsafe, which can and should be restricted.

He talks to Nick about why he ended up so passionate about this subject, and warns of society falling into an "abyss" of political violence.

Producer: Daniel Kraemer