Marijuana use impairs the ability to function effectively and safely on the job and increases work-related absences, tardiness, accidents, compensation claims and job turnover and is associated with lower academic grades. Teens who use marijuana daily are 60 percent more likely to drop out of high school than those who don’t use.

Employees may argue that using marijuana on their own time shouldn’t affect their jobs. However, the effects of marijuana last up to four hours after use. Marijuana significantly affects productivity in the workplace, causing a slower reaction time, loss of coordination and balance, short-term memory problems, an inability to perform tasks that are complex and changes in sensory perception. Marijuana affects each person differently depending on their mood, weight and personality type, but it is dangerous in the workplace.

Marijuana use in the workplace can affect employers both adversely and directly. Marijuana use is still illegal under federal law, so any employer that receives federal funding or is subject to testing for safety-sensitive workers must continue to prohibit marijuana among employees. There may also be a litigation risk related to marijuana that affects employers. Defending an employment practices liability suit can cost employers up to $107,000.

Employees that use marijuana may exhibit many of the general health problems that affect tobacco smokers. Marijuana users may suffer from a persistent cough, frequent acute chest illnesses and an increased risk of lung infections. Each of these instances can lead to the employee requiring time off work or reducing their productivity.

Employers should be concerned that students who use marijuana will not be prepared to flourish in the workforce in the future. A study by the non-profit RAND Corporation, published in the journal Addiction, found that students who used marijuana and alcohol in middle school and high school struggled with poor academic performance and mental health problems. Marijuana use was tied to an even broader spectrum of problems, including increased delinquent behavior and decreased preparation for academic success.

Both legalization and increased use may result in a reduced pool of qualified job candidates. According to the U.S. National Survey on Drug Use and Health, youth with poor academic results were four times more likely to have used marijuana in the past year when compared with youth that had higher grades. In fact, heavy marijuana users report that use of the drug resulted in negative effects on their cognitive abilities, social life, career status and physical and mental health.