As Californians prepare to vote on Proposition 19 on Tuesday, many disagree whether the recreational use and commercial sale of marijuana should be legalized, while voters and employers question its regulation in the workforce.

More specifically, opponents question the exact meaning of “actual impairment.”

“No person shall be punished, fined, discriminated against, or be denied any right or privilege for lawfully engaging in any conduct permitted by this Act or authorized pursuant to Section 11301 of this Act. Provided however, that the existing right of an employer to address consumption that actually impairs job performance by an employee shall not be affected,” Prop. 19 reads.

This means employers don’t have the right to prohibit a school bus driver from “toking up” before work and driving impaired, said Bill Cirone, Santa Barbara County’s superintendent of schools.

“This is an issue of public safety,” Cirone said. “A school bus driver could be forbidden to smoke on school grounds but could show up with marijuana in their system.”

Opponents of Prop. 19 argue that there must be an accident before an employer could prove that an employee’s drug use compromised safety or impaired performance, according to California Chamber of Commerce legal experts.

Brendan Huffman, executive director of the Chambers of Commerce Alliance of Ventura & Santa Barbara Counties, said anti-smoking laws don’t apply to cannabis so an employee could even light up in the workplace.

“(Employers) would be powerless to prevent, reprimand or fire someone from that activity,” Huffman said. “As a result, they don’t want customers coming in to the smell of marijuana and they don’t want to be paying people to do their best work while impaired.”

But Prop. 19’s proponents disagree. They argue that legalization will not change the law that “forbids impairment while engaging in dangerous activities such as driving.”

“This act is not intended to affect the application or enforcement of the following state laws relating to public health and safety or protection of children and others … nor any law prohibiting use of controlled substances in the workplace or by specific persons whose jobs involve public safety,” the proposition reads.

Yet, CalChamber legal experts contend the proposition would give marijuana smokers “special protections” because drug testing would “immediately expose the employer to litigation” as a result of discrimination implications.

On the contrary, proponents say the measure wouldn’t change anything at all for employers, who would still be able to take disciplinary action against workers under the influence whether it’s marijuana, prescription pills or alcohol.

Proponents, such as the National Organization for the Reform of Marijuana Laws, also say that the means of taking disciplinary action results from a urine test is an unreliable practice. It’s possible to pass a urine test while high because tetrahydrocannabinol (THC) doesn’t show up in the system until hours after smoking, and proponents say more accurate blood tests should be used.

If the right strands are used responsibly, said Dr. Steve Hosea, Santa Barbara Cottage Hospital’s associate director of internal medicine education, marijuana use doesn’t alter a worker’s ability.

“People can medicate with cannabis without becoming high from it,” he said. “The two are not necessarily guaranteed from using cannabis, especially some of the newer plants that are more likely to give you a therapeutic remedy than getting high.”

The difference between the two lies in the balancing of therapeutic cannibinoids versus the THC concentration that provides the “high” sensation, said Hosea, who added that the medical industry is just beginning to learn which cannibinoids provide the particular therapeutic effects.

“Many people know how much to use to get pain relief and not be distracted from their ability to do their job,” he said.

It’s the employee’s and employer’s responsibility to discuss their medication; if it impairs their ability, no matter what the medicine, they should find another job, he said. Hosea said a colleague used marijuana “three to five times a day to treat chronic pain” and led a very successful life until he died several years ago.

Aside from workplace safety, CalChamber legal analysts found that the proposition would cause employers to lose millions of dollars in federal grants because they wouldn’t be able to comply with federal laws that require a drug-free workplace. Also, workers would face harmful exposures that employers would be liable for, Huffman said.

“They would be subjecting employees to second-hand smoke that will get them high if they inhale enough of it, as well as, risking public safety,” he said.

Proposition 19 would allow adults age 21 or older to possess up to an ounce of marijuana for personal consumption, grow plants on up to a 25-square-foot parcel per private property, or transport marijuana for personal use. Local governments may authorize larger amounts for personal use, commercial use, transportation and sale. It would allow local and state governments to tax marijuana possession, cultivation and distribution, according to the Secretary of State’s Web site.

In California, voter-approved Proposition 215 legalized licensed individuals or businesses to cultivate marijuana for medical purposes in 2006. However, federal agencies have the jurisdiction to prosecute California patients and providers of medical marijuana. Marijuana use would still be illegal under federal law even if Proposition 19 is approved Tuesday.

The measure would prohibit marijuana at school, using it in public, smoking with minors present or driving while impaired.

The campaign to pass the proposition has received a $1 million contribution from billionaire George Soros, chairman of a hedge fund and founder of the Open Society Foundations. He’s the campaign’s largest donor behind Richard Lee, an Oakland medical marijuana entrepreneur, who spent $1.5 million.

Gov. Arnold Schwarzenegger, who opposes legalization, has downgraded possession of an ounce or less of marijuana from a misdemeanor to an infraction. The legislation, which he signed last month to save the state legal expenses, will take effect Jan. 1.

Meanwhile, the latest Field Poll found support for Prop. 19 apparently eroding. The survey, released over the weekend, found that likely voters were opposed to Prop. 19, 49 percent to 42 percent.

— Noozhawk intern Alex Kacik is a graduate of Cal Poly, San Luis Obispo. He can be reached at akacik@noozhawk.com. Follow Noozhawk on Twitter: @noozhawk or @NoozhawkNews. Become a fan of Noozhawk on Facebook.