Clen attended Hillhead High School in Glasgow before taking his Master of Arts and LLB in Glasgow University. He completed his Diploma in Legal Practice in 1996 and then joined Macarthur Stewart Solicitors in Oban where he practised between 1996 and 2001.
He has practised in the litigation department of the firm for the last 20 years. He is a member of Lurgan Rugby Club. He is an ex-professional musician and also a bus driver with an enduring interest in vintage buses. He is a member of the actors’ union Equity.