When I started each of my last 2 jobs, I had to take a drug test. They are both US Fortune 500 companies. They are just normal computer operations type jobs.

The previous company won their case in Colorado Supreme Court to fire someone using medical marijuana even while off-duty.[0]

Additionally, even though we passed a law (constitutional amendment) allowing recreational use in Colorado, employers are still allowed to test and fire you for it.

[0] https://ogletree.com/insights-resources/blog-posts/colorado-...