Monitoring Employees through drug testing
With regard to drug or other substance testing, the employer has a strong argument in favor of testing based on the law.
Since the employer is often responsible foe legal violations of its employees committed in the course of their job, the employer's interest in retaining control over every aspect of the work environment increases.
Employees may argue that their drug usage is only relevant if it impacts their job performance.
Until it does, the employer should have no basis for testing.