You will have read that one of Great Britain's Olympic medal hopes, Tom Daley, was subjected to considerable abuse over Twitter, after finishing fourth in the men's synchronised 10m platform diving event on Monday. Daley received offensive tweets about his late father from a Twitter user who has subsequently been arrested.

As the use of social media increases, so too does the potential for harassment through online networks. Employers should be aware that they could be affected by the actions of their employees online. Even if the online comments are posted out of working hours, they may well be seen to be harassment by that individual and if they are your employee then your company may be vicariously liable if the recipient is another employee.

Furthermore, the House of Lords decision in Majrowski -v- Guy's and St Thomas' NHS Trust in 2006, held that employers can be vicariously liable under the Protection from Harassment Act 1997 for acts of harassment committed by an employee in the course of employment. This has considerably widened the scope for employees to make claims against their employer where a colleague has pursued a course of conduct that causes the employee alarm or distress.

Given the increased use of social media and the difficulty of controlling how employees interact with each other through its various forms, employers would be well advised to implement a detailed policy that regulates the use of social media by employees both within and outwith the workplace (so far as it may affect the employer). We have found this to be a particular issue for employers that engage employees to work unsupervised on nightshift and have access to the internet as part of their role.