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What Is a Controlled Substance?

The National Cancer Institute defines a controlled substance as:

"A drug or other substance that is tightly controlled by the government because it may be abused or cause addiction. The control applies to the way the substance is made, used, handled, stored, and distributed. Controlled substances include opioids, stimulants, depressants, hallucinogens, and anabolic steroids."

Federal and state governments regulate these substances by forbidding or restricting their availability to the public. An ordinary person caught possessing a controlled substance can be arrested by law enforcement. They may be charged with a crime and subjected to fines or imprisonment.

This article discusses federal and state controlled substance laws and the crimes associated with them.

Is Possessing a Controlled Substance Always Unlawful?

Not all controlled substances are illegal in all circumstances. Many are sold through pharmacies for legitimate medical treatment. See the federal controlled substance schedule and your state's laws to determine whether possession of a drug is illegal.

Controlled Substance Schedules: Which Drugs Can I Legally Possess?

The Controlled Substances Act (CSA) of 1970 assigned controlled substances into five categories. While new substances have been added to the list, the categories (or schedules) remain the same. The list is updated annually, so check to see the most updated schedules.

  • Schedule I substances are said to have a high potential for abuse, no currently accepted medical use, and lack an acceptable level of safety for use under medical supervision. This category includes hallucinogens, cannabinoids, heroin, LSD, marijuana, peyote, and ecstasy. Regardless of classification, some of these drugs are used for medical treatment (medical marijuana and opiates). LSD is the subject of legitimate medical research. Peyote has been used by some indigenous peoples of the Americas for millennia, and its use in religious ceremonies is federally protected. However, that protection does not exist under state law in many states.
  • Schedule II substances are said to have a high potential for abuse and usage can lead to severe psychological or physical dependence. These substances do have a currently accepted medical use in the United States. Examples include Dilaudid, hydrocodone, Demerol, OxyContin, Percocet, morphine, fentanyl, and codeine.
  • Schedule III substances stimulate the central nervous system but have less potential for abuse. Their use can still lead to moderate or low physical dependence and high psychological dependence. These drugs include amphetamine and methamphetamine, Tylenol with codeine, ketamine, and anabolic steroids.
  • Schedule IV: These substances have a lower potential for abuse than Schedule III drugs. In practice, Schedule III and IV drugs are treated similarly. They can only be obtained by prescription. Schedule IV drugs include Xanax, Soma, Klonopin, Valium, Ativan, Versed, Restoril, and Halcion.
  • Schedule V: These contain limited quantities of narcotics such as cough syrups with codeine. Some of these substances are legally available without a prescription.

Is it Illegal to Possess Scheduled Drugs?

Technically, it is illegal to possess any of the drugs listed on the schedules. There could be a defense, however, if a medical professional prescribed the drug and it was lawfully purchased.

Penalties for drug offenses vary greatly, depending on:

  • The type and quantity of drug
  • Whether the drug was possessed for personal use or sold or distributed (drug dealing)
  • Whether the defendant was charged by state or by federal authorities

Federal penalties are notably severe. A federal charge for possessing 500 to 4,999 grams of cocaine carries a five to forty year prison sentence and a fine of up to $5 million dollars. Aggravating factors like a prior conviction or a death or serious injury from the drug use could result in life imprisonment and higher fines. The U.S. Drug Enforcement Division (DEA) provides charts illustrating drug trafficking penalties.

State and Federal Controlled Substances Laws: Which Applies?

If there is a conflict between a state and a federal law, the federal law takes priority. This is established by the Supremacy Clause of the United States Constitution. The Controlled Substances Act is a federal law, so it applies regardless of state laws.

States are allowed flexibility in how they enforce (or do not enforce) drug laws. Some states have stricter laws than the federal government. Others have reduced penalties and focus more on providing avenues for substance abuse treatment for addicts.

Cannabis Regulation

Regulation of marijuana and cannabis products is perhaps the fastest changing field of criminal law.

Since 2013, the federal government has largely chosen not to interfere with state marijuana policies. Marijuana possession remains technically illegal in all fifty states. And yet most states allow the use of "medical marijuana" and cannabis products.

As of 2021, the sale and use of marijuana for recreational purposes is legal in 18 states and the District of Columbia. Thirteen states have decriminalized its use in small amounts, purchased legally. In only one state are cannabinoids illegal in all forms and for all purposes — Nebraska.

Texas is a good example of a state in the process of change. While marijuana is illegal, police in Austin are not arresting people for possessing less than four ounces. Several other cities in Texas "cite and release" people who possess small amounts.

Crimes Associated with Controlled Substances

Under the CSA, it is unlawful to do the following with a controlled (or counterfeit) substance:

  • Manufacture
  • Distribute (import, export, or traffic)
  • Dispense
  • Possess with intent to manufacture, distribute (import, export, or traffic), or dispense
  • Attempt or conspire to do any of the above

State laws vary widely. Check the laws of your state at the National Association of State Controlled Substances Authorities. Go to the bottom of the page to select your state.

More Questions About Controlled Substances? Ask an Attorney

Are you facing criminal charges for possession of a controlled substance? Are you wondering whether you can legally travel with your own prescription medication? Talk to a local criminal defense attorney to understand how state and federal laws may apply to you.

You Don’t Have To Solve This on Your Own – Get a Lawyer’s Help

Meeting with a lawyer can help you understand your options and how to best protect your rights. Visit our attorney directory to find a lawyer near you who can help.

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