Companies that employ security personnel must make workers understand how they could be in breach of health and safety regulations if they take action against a suspected perpetrator.

That's the warning from health and safety advisor and employment law specialist Bibby Consulting & Support following a case in which a security officer lost his job after tackling a shoplifter.

Working at an HMV high street store in Sutton, South London, the guard saw a youth leaving the shop with 20 stolen DVDs. After a chase through the shopping centre the offender was caught and taken back to the store. But the guard was later sacked, partly because the company's health and safety policy stated that security guards had to avoid confrontations with suspects that could develop into something more serious. HMV introduced the ruling nationwide after an employee was stabbed to death while catching a thief.

Even though the company said that in the Sutton case the guard was asked to leave "for an...