Prudent employers will have an alcohol and drug policy in place.  That policy usually states that alcohol or drug misuse is a disciplinary offence, and often such policies make it clear that a breach of the company’s alcohol/drugs rules will warrant summary dismissal.  In addition, employers often reserve the right to carry out random alcohol/drug tests.

In some jobs, even a trace of alcohol or drugs in an employees’ system is considered to be a serious disciplinary offence, especially where there is deemed to be a risk to customers.

A recent case in the employment tribunal shows that where an employee’s test is positive and the employee offers an explanation as to why that should be the case, the employer has a duty to carry out a reasonable investigation into the reasons given by the employee.

In this case, a bus driver in Bristol was dismissed after his saliva tested positive for cocaine.  The bus driver said that he had been counting large sums of money and that he had eaten sandwiches just before taking the drug test.  During the case it emerged that up to 88% of bank notes in the UK carry traces of illegal drugs.  A study by the Forensic Science Services in 2010 found that almost every British bank note in circulation is likely to contain traces of cocaine, and that 1 in 20 notes are likely to give a significant reading.

The driver also argued that the saliva test was unreliable and he went on to spend £440 of his own money on having a more accurate test done.

During the tribunal hearing an expert witness said that the initial positive cocaine result was down to “sample contamination” as a result of the employee handling the bank notes before he ate the sandwiches.  The tribunal decided that the employer had not conducted a proper investigation into the explanation given by the employee and thus found that the dismissal was unfair.

This case is a reminder to employers that they must have detailed policies on rules relating to drugs in the workplace and they must consider any explanations given by an employee who tests positive.  However, recent cases that have reached the Appeal Courts have indicated that although an employer has a duty to investigate reasonable explanations, he is not under an obligation to investigate every possible explanation that his employee might put forward.

This case illustrates the difficulties faced by employers in such situations.  Different tribunal judges are very likely to have different views on what amounts to a “reasonable investigation” or for that matter, a “reasonable explanation”! 

Reggie Lloyd
01206 217347
reggie.lloyd@birkettlong.co.uk