The National Drug-Free Workplace Alliance says small businesses bear the greatest burden of substance abusers. Why? Drug users don’t apply to jobs at large companies, which traditionally have established, companywide policies regarding drug use. Instead, they may seek employment at small companies with fewer resources (and motivation) to perform tests.

If you don’t drug-test employees, your business could be at risk for negligence lawsuits from customers and employees. For example, if an employee high on cocaine stumbles and falls, injuring a co-worker or customer in the process, your business could be sued for negligent hiring. The plaintiff could say, “Why didn’t you drug-test?”

If you’re thinking about drug testing your employees, here are five legal considerations:

1.    If you test one, you should probably test all. The law does not explicitly say businesses that drug-test must test all their employees. Yet if you don’t, you open up your business to a host of anti-discrimination. Say, for instance, you test only employees you suspect of using drugs—someone might construe this as singling out certain people based on income level, race, gender or other protected status.

2.    If you receive federal funds, drug testing is required. The Federal Drug-Free Workplace Act requires businesses with $100,000 or more in federal contracts to test all of their employees for drug use. This also applies to businesses that receive federal grants.

3.    In order to test job applicants, you may be required to first offer employment. If your business employs 15 or more people, it must follow the Americans With Disabilities Act, which makes it illegal for any employer to test a job applicant without first making a conditional offer of employment.

4.    Test honestly. Don’t try to get a specimen sample from an employee or job applicant without his or her consent—this is unlawful.

5.    Don’t forget state-specific laws. Each state has its own set of rules and regulations regarding employee drug testing. In Illinois and Virginia, for example, businesses cannot require employees or job applicants to pay for testing themselves. For drug laws specific to your state, check with the U.S. Department of Labor. Each state also has its own Drug-Free Workplace program—if you follow the rules and requirements outlined in these programs, you’re afforded certain protections.

— National Federation of Independent Business