NEW YORK (CBS NEWS) – Most employers screen job applicants for marijuana use, even in states where it’s legal for medical and recreational use. That has some experts arguing that the practice is a waste of time and removes otherwise qualified candidates from consideration for jobs.

About 78 percent of the clients of First Advantage, the world’s largest provider of employment screening services, do not “accept” medical or recreational marijuana in the states were it’s legal, according to Josephine Kenney, the company’s chief global compliance officer, who cited an internal analysis of clients.

(credit: Kenzo Tribouillard/AFP/Getty Images)

“They are continuing to stay the course,” she said. “Look, they need to balance the risk here … even with a marketplace where the unemployment rate is really low. They still want productive employees. They still want employees that are going to be safe.”

According to executive outplacement firm Challenger, Gray & Christmas, which favors eliminating marijuana preemployment screening, companies are finding it increasingly difficult to find qualified applicants who don’t smoke weed at a time when unemployment is at a 17-year low.

“While it is good policy to ban drugs and alcohol in the workplace, what workers do after hours — as long as it does not impair the company’s operations or productivity, or otherwise do harm — should not have any bearing on how workers are viewed by their employers,” Andrew Challenger, a vice president at the firm, said in a press release.

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