Employees under the influence of alcohol or drugs while at work pose a danger to themselves and those around them. Maintaining a comprehensive drug and alcohol policy that provides for limited substance testing can help to manage this risk, but there are important legal requirements with which employers must comply. Every individual in the State of California has a constitutionally protected right to be free from unreasonable searches and seizures. Courts have consistently held that this right applies to private sector employers and limits the ability of employers to engage in substance testing of its employees. As a general rule, employers may drug test workers before and immediately after hire without any suspicion of drug use. However, once an employee has been hired, employers must generally have “reasonable suspicion" of drug or alcohol use before requiring the employee to submit to substance testing of any kind. Random employee substance testing is “suspicionless testing," and is therefore illegal with certain limited exceptions. The most notable exception to the prohibition of random substance testing relates to employees in “safety sensitive" positions. Reasoning that the assurance of public safety outweighs the privacy interests of individual employees, California courts have held that random substance testing of employees in “safety sensitive" positions is permissible. “Safety sensitive" positions are generally regarded as positions in which an on-the-job error can result in substantial harm to co-workers or private parties. The determination of whether a job is “safety sensitive" must be made on a case by case basis and depends on the unique facts of the situation, but generally speaking, any job that can result in serious bodily injury or death if improperly handled (i.e. a heavy equipment operator or truck driver) will qualify. In addition to restrictions on when an employer may conduct substance testing, the law also regulates the means by which employers may administer such tests. In general, employers must conduct substance tests in a private setting and share the results only on a “need to know" basis. Substance testing also raises potential issues involving disability discrimination if an employee is punished for using prescribed medication, such as opiates, so it is important to have a written substance testing policy which clearly delineates actionable versus non-actionable “positives." If you are considering implementing a drug and alcohol policy that includes substance testing, consultation with a local employment attorney would be strongly advised. Such a policy can be an effective means of ensuring workplace safety and managing liability, but if improperly formulated can be a trigger for litigation.