Apart from the rail industry, where drug testing is allowed by the Transport and Works Act 1992, the use of screening is a legal minefield.
According to an employment specialist, in theory any company can impose substance misuse testing but it can be extremely tricky to implement.
Even if an employer has it written into a contract, it is still no guarantee that it is does not contravene the human or employment rights of the worker.
The difficulty arises because drug testing involves taking a hair, saliva, urine or blood sample from an employee and that needs consent.
Taking it forcibly would amount to a physical assault. If an employee refuses to allow the testing, they may claim any subsequent action resulted from an infringement of their rights to privacy, which is protected under the Human Rights Act of 1998.
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