Yes! In several provinces occupational health and safety legislation actually mandates that workplaces institute a proper harassment and violence policy, usually including workplace sexual harassment under that definition as well.
While the legislation itself does not say exactly what form these policies must take, there are other rules, such as training staff on these policies, making sure they are readily available for reference, and making sure that they are updated semi-regularly. This policy should clearly define harassment, and set out how an individual can make a complaint of harassment. The policy should also outline how any reported incidents will be dealt with, including what investigation procedure will take place, and how anyone involved may expect to be dealt with.
A workplace harassment policy should never just be a ‘nice to have’ that sits in a drawer for years. These are living, breathing policies that need to be followed closely in order to properly protect your workplace in the event of a legal claim. While provincial labour ministries may be able to offer sample policies, it is always best to work with an employment lawyer to tailor and implement a policy that properly protects your business.