Independent contractors and employees are treated very differently by the Canada Revenue Agency (and other adjudicative bodies such as employment standards tribunals and the courts) and misclassification can be costly. If the tax agency determines an individual is an employee rather than an independent contractor, the employer will have to pay CPP and EI premiums and may be charged penalties and interest.
BDO Dunwoody’s article explains the complicated issue of properly determining the status of people who do work for you.
http://www.bizactions.com/index.cfm/ba/e100/fa/81126937G627J357168P77P3958T1/