Medical marijuana deductions for food stamps are up in smoke following an order from the feds.

States have received instructions from the United States Department of Agriculture to cease medical marijuana income deductions for food stamps — that were already prohibited under federal law.

Prior to the edict, quietly issued in mid-July, some states with statutory provisions giving doctors the ability to prescribe medical marijuana had allowed applicants to deduct the marijuana expenses from their incomes to qualify for the Supplemental Nutrition Assistance Program, or food stamps, based on a provision in the 2008 Food and Nutrition Act which allowed deductions of “allowable medical expenses” for households with elderly or disabled members.

According to the memo sent to all regional directors of SNAP, USDA’s Food and Nutrition Service has had a “long standing policy that a household may not utilize the SNAP medical deduction for the cost of any substance considered illegal under Federal law.”

“States that currently allow for the deduction of medical marijuana must cease this practice immediately and make any necessary corrections to their State policy manuals and instructions,” the director of the Food and Nutrition Service’s Program Development Division, Lizbeth Silbermann, wrote in the memo. “Cases that cannot be readily identified must be corrected at the time of recertification or periodic report, whichever is sooner. States that are not in compliance may face penalties for any over issuance of SNAP benefits.”

While the memo explains that 18 states have provisions allowing for medical marijuana, three states, which had previously given applicants the ability to use the deduction, were affected by this edict — Maine, Oregon and New Mexico.

Maine’s Department of Health and Human Services spokesman John Martins explained to The Daily Caller that Maine has now ended all such deductions.

“As soon as we received the guidance from the feds, that we could not continue on we dropped that from the program,” Martins said, adding that the order only affected ten Maine SNAP recipients.

Gene Evans, spokesman for the Oregon Department of Human Services told The Oregonian, in advance of the policy adjustment, that with medical marijuana available legally since 1998, the deductions in Oregon had been long standing.

“Medical marijuana gets treated just like any other prescription drug,” Evans told The Oregonian, explaining that while the deductions are uncommon about 8 percent of food stamp recipients were eligible for the deduction.

Matt Kennicott, communications director for New Mexico’s Human Services Department, told TheDC that the state is having little difficulty complying with the order, as SNAP applicants in the state had not been using the deduction, despite its availability.

“In the past we might have allowed for the deduction but nobody ever used it,” Kennicott said.

While USDA issued their order to end marijuana deductions last month, according to the memo there has always been a federal ban on the practice.

“Under the Controlled Substances Act, 21 U.S.C.§801 et seq., marijuana is a Schedule I controlled substance that has no currently accepted medical use and cannot be prescribed for medicinal purposes. 21 U.S.C. § 812(b)(1), (c). SNAP is a Federal program and must conform to Federal law regarding illegal substances,” Silbermann explained in the memo. “Therefore, marijuana and other Schedule I controlled substances are not “allowable medical expenses” under Federal law.”

When asked to clarify if USDA knew how long states had been issuing medical marijuana deductions for SNAP an agency spokesperson directed TheDC back to the initial letter.

“As stated in the letter, this letter reaffirms longstanding USDA policy that a household may not utilize the SNAP medical deduction for the cost of any substance considered illegal under Federal law,” USDA spokesperson Alyn G. Kiel wrote in an email.

UPDATE: After publication, John Martins emailed TheDC to explain that information he had offered for this report — that Maine allowed the deduction for anybody who had received a doctor’s order for medical marijuana, not just the elderly and disabled — was incorrect. The story has been updated to reflect the new information.

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