I'm subject to drug testing (including alcohol). Regardless of whether it's illegal or legal drug use, most companies don't won't to take the risk of employing someone who might have a problem, especially those failing urine testing as it implies you would turn up for work with drugs in your system like you did for your pre-job medical.
Jokester
same here both alcohol and drug. Legal or illegal.
It's more to do with safety and insurance, rather than personal problems.
i'm even meant to tell my manager if I've taken any drugs even asprin/hayfever etc. Which is then looked up on a system for side effects and then limits can be placed on what I can do at work.