Rebecca Masterson wanted to become a licensed foster mom. Earlier this month, the Phoenix lawyer took in 16-year-old Johnny*, who she met while volunteering. Becoming licensed would help her pay for groceries, clothes and start a savings account for the teenager.

But when Masterson applied to become Johnny’s foster mom, she was rejected by the Arizona Department of Child Safety (DCS) for admitting to having a medical marijuana card.

Masterson obtained a medical marijuana caregiver card to treat her adopted 12-year-old son’s muscle spasms. After exhausting all other pharmaceutical options, she discovered cannabidiol (CBD), a non-psychoactive extract of marijuana, which she says has drastically reduced her son’s spasms.

“I have no alcohol in my house, but they did not ask about that,” Masterson said. “They only asked about the medication.”

The two main extracts from cannabis are tetrahydrocannabinol (THC) and CBD. THC is responsible for the “high” most commonly associated with marijuana, while CBD couldn’t give you a buzz if you wanted it to. Both cannabinoids are medicinal, but because CBD is also found in hemp, it is legal in most states and is available over-the-counter, including at Target.

Following a story in the New Times and some back-and-forth with her licensing agency, Masterson was able to reverse DCS’ decision by explaining that CBD is non-psychoactive. Her license is still pending. But it’s an indicator of some of the barriers many hopeful foster parents may face.

The state’s reasoning is that cannabis is still considered a Schedule I drug under federal law, meaning the feds don’t recognize any medical value and claim cannabis has a high potential for abuse. This theory is not shared by the 29 states that have enacted MMJ programs since 1996.

Still, Arizona won’t license any foster parents who use medical marijuana, even though it is essentially a prescription and in spite of numerous Arizona court rulings that say the state’s medical marijuana program does not conflict with federal law.

“Congress itself has specified that the CSA [Controlled Substances Act] does not expressly preempt state drug laws,” the state Supreme Court wrote in a 2015 ruling. “There is no such conflict here.”

This stipulation only applies to licensed foster parents — unlicensed parents have no card exemptions. The number of families rejected for this reason is “extremely rare,” according to Darren DaRonco, the public information officer for DCS. But potential foster parents with medical marijuana cards don’t even get to the rejection stage because once they learn of the policy, they often stop their application process.

Russ Funk, Director of Community Engagement for Aid to Adoption of Special Kids (AASK), said his agency began seeing medical marijuana-related rejections when the policy was first implemented around 2012. But once AASK began letting potential parents know in advance about this policy, they noticed many with medical marijuana cards stopped moving forward with the process altogether.

“We have not submitted a study for a family who’s had a medical marijuana card in quite some time,” Funk said. “[We ask] are you ready to go through a six-month process for nothing? Are you going to go through 30 hours of pre-service training, another three hours of additional training, invest all this time and energy, when you know it’s not going to be accepted? And when we present it that way to folks in this situation, they’re opting out.”

Data on this sort of thing is not kept, so it’s not easy to find numbers on the exact amount of medical marijuana-related application dropouts. However, Arizona has more than 132,000 medical marijuana patients, the majority being older than 30. Would any of them make decent foster parents for the nearly 18,000 kids in foster care in Arizona?

Oddly enough, DaRonco said it doesn’t actually matter if you have a card — only if you admit to using cannabis.

“If they do say that they have a medical marijuana card and they say no, I don’t actually use it right now, we just take them at their word,” DaRonco said in a phone call. “We don’t drug test them or anything like that.”

In other words, it’s not difficult to lie about this sort of thing.

“I didn’t know that everyone lied about this,” Masterson, the woman applying to be a foster mom to 16-year-old Johnny, said. “And that’s not in my nature, so when they asked about medications in the household, I told them about the CBD oil and that I did not use it [for myself].”

In his 11 years working at AASK, Funk said he’s heard many stories of families withholding information on a variety of topics.

“There’s dozens of barriers between wanting to help a child in foster care and actually being licensed to do so,” Funk said. “This is just another one of those. To whatever degree any of those barriers can be reconsidered and reevaluated, I think that would be a good thing.”

DCS is working with the Department of Health Services to reconsider their policies, at least on CBD, according to DaRonco, but it’s unclear when these rules will take effect or if they will have any meaningful impact on medical marijuana patients.

The Office of Registration and Licensing, Southwest Human Development (which handled Masterson’s case) and several other foster care licensing agencies did not respond to a request for comment.

*Johnny’s real name is not being used.

Troy Farah is an independent journalist from California. His reporting has appeared in The Outline, VICE, Fusion and others. He can be followed on Twitter and troyfarah.com