INDIANAPOLIS -- Indiana's Attorney General Curtis Hill has declared CBD oil illegal in the state of Indiana.

AG Hill made the declaration in an advisory opinion issued Tuesday.

Cannabidiol hemp oil, or CBD oil, is used by families of children with seizures and by others who deal with chronic pain and anxiety.

It was officially listed as a Schedule I drug by the Drug Enforcement Administration in December 2016, but there was confusion in the state of Indiana as to whether or not it was exempted by another law.

"Schedule I drugs, substances, or chemicals are defined as drugs with no currently accepted medical use and a high potential for abuse," the DEA says on its website.

The Schedule I ruling put the oil in the same category as heroin, LSD, ecstasy, meth, peyote and marijuana. Hill cited on Tuesday that federal ruling as a primary reason for his opinion.

Despite the ruling, CBD oil remained on shelves of some stores that sell health supplements, such as Fresh Thyme, throughout 2017.

It also continued to be used by those who were named to a registry authorized by the Indiana legislature for certain physicians and caregivers to use hemp oil for children with intractable epilepsy. It was also to encourage the further study of its use in treating the epilepsy.

RELATED | Bill introduced to create registry for CBD oil users

That registry can help people like Brian Bennett, whose 8-year-old son was diagnosed with epilepsy. At one point Bennett's son was having up to 200 seizures a day.

Bennett said his son had to wear a helmet, because he would fall and hit his head. He broke 24 of those helmets, until his parents discovered CBD oil.

Bennett would travel as far as Colorado to obtain the oil to help his son cope.

It is unclear how AG Hill's ruling will affect the registry. The law for those on the registry remains in place, Hill said in his ruling, but there is uncertainty of how those patients will get access to the drug if stores will be cited for selling it.

CBD oil is made from hemp, a plant that has little or no THC and cannot cause a high at all, unlike its cannabis cousin marijuana.

Indiana excise officers began cracking down on the sale of the oil in May, but reached a head in August when the murkiness over its legality came in the form of citations that were issued to stores selling the oil, and then later forgiven.

Some lawmakers and the Indiana State Police said the substance was already legal under a 2014 law that removed industrial hemp products from the state’s controlled substance statute.

AG Hill's ruling clarifies the product is illegal in the state of Indiana, and could potentially lead to criminal charges for anyone selling or using the product.

“The manufacture, possession, use and sale of cannabidiol – and substances, food products or edible oils containing cannabidiol – are unlawful under both Indiana and federal law," Attorney General Hill said in his opinion released Tuesday. "Any individual possessing a substance containing cannabidiol – or anything packaged as such – in plain view of a law enforcement officer is subject to having that property seized. Only upon showing that one meets the limited conditions under Indiana law could one expect to avoid being prosecuted under Indiana law. Further, no one in Indiana is authorized to sell cannabidiol or any substance containing cannabidiol under state or federal law.”

You can read AG Hill's full opinion below:

“Over recent weeks, I’ve worked with my staff to develop an advisory opinion regarding the status under Indiana law of the chemical compound cannabidiol – better known as ‘CBD.’ Cannabidiol is one of the most prevalent chemical compounds in the cannabis plant, otherwise known as marijuana. “This issue has drawn public attention this year following law-enforcement actions against Indiana stores marketing and selling ‘CBD oil,’ a substance delivered to consumers in dropper bottles, sprays or mists – all generally to be taken orally. “My task at this juncture is not to express my personal view of what I believe the law ought to stipulate. My task, rather, is to help provide clarity regarding what the law already says as written. “There is no doubt, as a matter of legal interpretation, that products or substances marketed generally for human consumption or ingestion, and containing cannabidiol, remain unlawful in Indiana as well as under federal law. “Indiana law does allow for a limited and focused exception created by House Enrolled Act 1148, signed earlier this year, aimed at individuals battling treatment-resistant epilepsy. This legislation pertains specifically to individuals properly added to the newly created Indiana State Department of Health Cannabidiol Registry. “Cannabidiol is classified under state and federal law as a Schedule I controlled substance because marijuana (Cannabis sativa) is a Schedule I controlled substance. State and federal laws that place cannabidiol in the category of a Schedule I controlled substance do not hinge on the degree or prevalence of pharmacological effects of a substance on a person. “The manufacture, possession, use and sale of cannabidiol – and substances, food products or edible oils containing cannabidiol – are unlawful under both Indiana and federal law. Any individual possessing a substance containing cannabidiol – or anything packaged as such – in plain view of a law enforcement officer is subject to having that property seized. Only upon showing that one meets the limited conditions under Indiana law could one expect to avoid being prosecuted under Indiana law. Further, no one in Indiana is authorized to sell cannabidiol or any substance containing cannabidiol under state or federal law.”

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