John Gilmore and Matthew Macdonald appear in Canadian Employment Law Today, writing on how the courts have again reminded employers–and arbitrators–of the importance of a proper investigation and analysis when an employee is discovered to be using medical marijuana contrary to the employer's policies. The law of medical marijuana continues to develop as employers are increasingly faced with employees choosing to use medical marijuana for various health conditions. Court reminds arbitrators and employers: Proper investigation of employee medical marijuana use a high priority