There are two distinct types of harassment that may be relevant here, each with a slightly different definition: harassment related to a protected characteristic; and sexual harassment. There is a separate basis for harassment where a worker is treated less favourably because they submit to or reject sexual harassment, but that is outside the scope of this article.
In the former, harassment occurs when someone engages in unwanted behaviour which is related to a protected characteristic that has the purpose or effect of violating another person's dignity or creating a degrading, humiliating, hostile, intimidating or offensive environment for that person. Sexual harassment has a similar definition and occurs when someone engages in unwanted behaviour of a sexual nature that has the purpose or effect of violating another person's dignity or creating a degrading, humiliating, hostile, intimidating or offensive environment for that person.
Employers will be liable for harassment by their employees that occurs in the course of employment, unless they can show that they took all reasonable steps to prevent the harassment. However, this can be a complex area and legal advice should be sought about the particular circumstances of any case. In some cases, it is relatively easy to identify that something has occurred 'in the course of employment' – for example, where one employee harasses another employee at the office. The issue becomes more complex where it relates to events outside of the workplace but connected with work – for example, an issue that occurs in the pub between two work colleagues, or between two colleagues at one of their homes.
For the "all reasonable steps" defence to apply, the steps must have been taken before the act of harassment occurred. Taking action in response to a complaint or allegation of harassment won't be sufficient. What are considered to be reasonable steps will vary depending on the nature of the employer, including its size and resources. However, the mere existence of an anti-harassment or equivalent policy alone will not be sufficient.
Reasonable steps generally include, but are not necessarily limited to, the regular review of any policy to ensure it remains fit for purpose; ensuring that employees are aware of any policy; appropriate training; and taking steps to deal effectively with any harassment complaints. Importantly, as the requirement is to take "all" reasonable steps, if there is anything else that the employer could reasonably have done to prevent the harassment, it will not succeed in running the defence.