With nearly half of the United States taking steps to legalize marijuana use, employers need to determine how they’ll react to these new laws.

For instance, in the state of Washington, a worker was initially fired for the use of marijuana, but then regained his position, according to NBCNews.com.  

Every employer needs a marijuana policy, according to Earle Miller, a counsel in employment law at White and Case in Los Angeles. But before implementing one, understand current laws regarding marijuana use.

Related: Why Colorado and Washington Were Wise to Legalize Pot

Colorado and Washington are the only states where possession and use of marijuana for recreational use is legal under state law. There are some states, such as New York and California, that have decriminalized marijuana possession.

Despite state laws, the possession and use of any amount of marijuana is illegal under federal law because marijuana is classified as a Schedule I drug under the Controlled Substances Act.

“Federal law applies everywhere in the U.S., including in those states that permit recreational or medical use of marijuana under state law," Miller explained in an email. "There aren’t really any states where marijuana is fully legal in the same way that tobacco is legal." 

Because of these new laws, people who live in states like Colorado and Washington might think it’s OK to show up to work stoned. This is why Miller strongly believes employers should revise the wording of their drug-use policies to expressly say "including marijuana."

Casey Sipe, an employment law attorney at Scaringi & Scaringi in Harrisburg, Penn., agreed. "In states where marijuana usage is legal, in whatever form, it could be equated to alcohol in the workplace. Employees are not permitted to work drunk, drink alcohol at work, or return from lunch drunk, so employees should not be permitted to work high," he said via email.

For employers who want to tighten up their policies and create a safer and more productive workplace, here are some things to consider when creating a marijuana policy:

Related: 4 Steps to Deal with an Employee's Substance Abuse Problem

1. Add consequences for the use of marijuana at work.

First and foremost, create a policy addressing the consequences of an employee’s marijuana use, just like the policy for the use of alcohol or drugs that are illegal.

Miller says most employers will want to prohibit the consumption of marijuana at the workplace, on company time or at the organization's functions. For example, if an employee arrives to work under the influence of marijuana or his or her work suffers because of its use, the employer would reserve the right to take disciplinary action against the employee.

Be careful, though, warned Jay Starkman, CEO of St. Petersburg, Fla.-based Engage PEO, a HR outsourcing organization. Certain states prohibit discharging, penalizing or refusing to hire lawful medical marijuana users based upon a positive drug test for marijuana unless the employee used, possessed or was impaired by marijuana while on the employer’s premises or during work hours.

"In Arizona and Delaware for example," he shared via email, "a positive test result alone will not provide the employer with sufficient grounds to discharge; the employer must have additional evidence that an employee was under the influence of marijuana while at work."

Sipe recommended when an employee has a valid prescription for medical marijuana, "evaluating the employee on a performance basis, as in their effectiveness completing their assigned duties, rather than by drug testing because testing would be pointless."

2. Don’t completely prohibit the use of marijuana at all times.

“Employers should probably be asking themselves whether they really need to have special marijuana policies that go beyond ensuring a drug-free workplace,” Miller said.

In other words, don’t create a policy that prohibits employees from using marijuana when they’re off the clock. Instead, focus on regulating on-the-job conduct and employee performance. Workers don’t want to feel like their employer is controlling their personal lives, so such a policy would not be good for the employer-employee relationship.

3. Be sure to include marijuana in any drug-testing policy.

Does the company have a drug-testing policy? Be sure to add marijuana to it. Bear in mind, however, state drug testing laws.

“[The] kind of drug testing an employer may have varies by state," Miller said. "Some states restrict drug testing to specific circumstances such as on reasonable suspicion.” 

Added Miller: “Colorado’s medical-marijuana law specifically says that employers are not required to accommodate the use of medical marijuana in the workplace.”

4. Make safety a priority.

When creating a marijuana policy, focus on safety. Especially for employers who have workers who operate heavy machinery, a stricter staff policy be needed.

“Employees who are under the influence of any substance at work can pose a danger to themselves, to co-workers and to customers and the public,” Miller said. “And employers will want to make sure they are not endangering any of those constituencies.”

Sipe equated the use of marijuana in the workplace to consuming alcohol. "If an employee's job involves driving, heights, explosives, dangerous machinery or any other situation where the employee's safety or the safety of others would be detrimentally affected if the employee is high, then marijuana use should not be tolerated, regardless of the state law on usage," he said.

View the Society for Human Resource Management's sample drug and alcohol policy.

Does your company have a policy about marijuana use?

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