“Harsh penalties do not deter people with substance use disorders from using drugs. People use drugs because they have a chemical dependence and often feel that they will not be caught,” the letter reads. “Believing that harsh penalties will deter drug use misunderstands addiction. Since the 1980s, we have had tough penalties for heroin use and distribution, yet heroin consumption has actually increased.”

The letter is signed by representatives from FreedomWorks, the American Conservative Union Foundation, Generation Opportunity, and Taxpayers Protection Alliance.

Under the law, if Sessions finds that banning a substance would prevent its abuse, he will be allowed to issue a temporary order adding it to “Schedule A,” a list of illegal substances, so long as the drug’s chemical makeup is “substantially similar” to that of a substance already on the list. (RELATED: Bill Allowing Jeff Sessions To Criminalize More Drugs Meets Massive Opposition)

While the conservative groups argue the power “misunderstands addiction,” Republican Rep. John Katko of New York, who introduced the bill, argues that the powers granted to the AG are essential because the Schedule A list needs to be able to adapt quickly to the development of new synthetic drugs.

“Currently, manufacturers and distributors of these substances are able to slightly alter the chemical structure of drugs to avoid law enforcement scrutiny and prosecution,” Katko explained in a statement when he announced the bill.

Aside from Sessions’ new power, the legislation adds 13 varieties of fentanyl to Schedule A, a hyper-potent synthetic drug increasingly mixed with heroin which can kill an adult with a dose as little as 3 milligrams.

The House Judiciary Committee will vote on the legislation Wednesday.

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