(ANTIMEDIA) In 2016, cannabis is still illegal in many parts of the country, and pharmaceutical giant Insys Therapeutics Inc., a manufacturer of fentanyl, just demonstrated much of the reason why.

Arizona is currently gearing up to vote on legalizing recreational cannabis. Ahead of that vote, Insys just contributed $500,000 in the fight against Proposition 205, U.S. News and other outlets report.

The Arizona-based pharmaceutical company recently gave the funds to Arizonans for Responsible Drug Policy, an anti-legalization campaign group actively fighting to defeat the ballot measure.

Insys’s contributions are particularly unsettling considering the company currently markets only one product — a spray version of fentanyl, a powerful opiate.

Fentanyl has become one of the country’s most dangerous prescription drugs. It is more potent than traditional addictive opiates, which already claim thousands of lives every year and drive addicts to graduate to heroin use. Fentanyl is 50 times stronger than heroin and has been linked to a growing number of deaths in the United States. It isparticularly dangerous when sold on the street and cut with other drugs. Fentanyl has been blamed for worsening the sharp rise in heroin overdoses as dealers across the country have begun adding it to heroin to make it stronger.

Yet Insys and opponents of legalization are more concerned about a plant.

According to Arizonans for Responsible Drug Policy, “four states and the District of Columbia have already legalized [cannabis] and are seeing disastrous repercussions for their youth, workplaces and communities.”

Of course, this assessment is incorrect.

Colorado has lower rates of teen cannabis consumption than the national average, and studies have shown driving while under the influence of the plant is far less dangerous than alcohol, a legal drug. Colorado has seen a spike intourism, business, and tax revenues as a result of legalization.

Interestingly, a study by Johns Hopkins university last year found states with medical marijuana had lower rates of overdose from opiates.

In spite of Arizonans for Responsible Drug Policy’s claims they care about communities, it is completely comfortable taking half a million dollars from a company that produces one of the most toxic and addictive drugs on the market. Unsurprisingly, Insys previously sold a synthetic cannabis product and has already gained approval from the FDA to launch a similar one in the near future. These business ventures provide an even deeper understanding of why they oppose legalization.

“[W]e are truly shocked by our opponents’ decision to keep a donation from what appears to be one of the more unscrupulous members of Big Pharma,” J.P. Holyoak, chairman of the Campaign to Regulate Marijuana like Alcohol said.

His statement continued:

“Our opponents have made a conscious decision to associate with this company. They are now funding their campaign with profits from the sale of opioids – and maybe even the improper sale of opioids. We hope that every Arizonan understands that Arizonans for Responsible Drug Policy is now a complete misnomer. Their entire campaign is tainted by this money. Any time an ad airs against Prop. 205, the voters should know that it was paid for by highly suspect Big Pharma actors.“

Considering the myriad healing properties of cannabis, it is obvious why a pharmaceutical company in the business of selling powerful painkillers is eager to invest in maintaining prohibition. Legalizing and normalizing cannabis pose a direct threat to pharmaceutical profits considering cannabis is effective at treating pain, anxiety, degenerative diseases, and potentially even cancer. Though much more research is needed to determine the true efficacy of cannabis as medicine, the federal government’s insistence on keeping it illegal stifles further scientific examination.

There are legitimate concerns about treating cannabis like alcohol — namely, that convoluted regulations make legalization a bureaucratic headache compounded by the substance’s illegal status with the federal government. Nevertheless, powerful interests are aggressively trying to keep cannabis illegal — Insys’s donation is the largest any group associated with Proposition 205 has received.

Around the country, the pharmaceutical fight against legalization is joined by the tobacco lobby, the alcohol lobby, the private prison lobby, and law enforcement.

Still, U.S. News reports the ballot measure is gaining popularity among Arizonans. While corporate cash has been known to influence election outcomes, only time will tell if Insys’s desperate attempts to keep a plant illegal will sway voters.