Wrong, you cant be made to take a test, however if refused, and the boss so to speak believes you should be tested, then he has the right to disapline and take you through the occupational health for a test, and maybe sack you.
You can't be made to take a drugs test, but if you refuse when your employer has good grounds for testing you under a proper occupational health and safety policy you may face disciplinary action, including being sacked.
Yes your right,i meant to say they cant force you to take a test,unless you've got something to hide it shouldn't be a problem.