What Is a Controlled Substance?

Federal and state governments regulate these substances by providing rules on public access. Law enforcement can arrest a person caught possessing a controlled substance. They may face drug possession charges and jail time or fines.

The National Cancer Institute defines controlled substances as substances the government tightly controls because of the possibility of abuse or addiction. They include opioids, stimulants, depressants, hallucinogens, and anabolic steroids. The government controls how the substance is:

  • Made
  • Used
  • Handled
  • Stored
  • Distributed

This article discusses federal and state controlled substance laws and their associated crimes.

Understanding Drug Crimes

Drug crimes often involve possessing, distributing, or selling controlled substances. The consequences can be severe — whether it involves prescription drugs or illegal drugs.

Drug Possession Charges and Penalties

Penalties for drug offenders may vary depending on:

  • The type of drug
  • The drug quantity
  • Whether the drugs were possessed for use, distribution, or sale
  • Whether the charges are brought under state or federal laws

A drug charge can lead to a felony conviction. Penalties for drug-related offenses range from first-degree to third-degree felonies. For instance, a federal charge for possession of specific drug quantities could result in prison time or fines. Drug possession cases may also lead to mandatory rehabilitation or drug treatment programs. This applies to states that emphasize rehabilitation over jail or prison time.

Is Possessing a Controlled Substance Always Unlawful?

Not all controlled substances are illegal in all circumstances. Pharmacies sell many for genuine medical treatment, necessitating a valid prescription. Authorities may deem it illegal if you possess prescription drugs or drug paraphernalia without a valid prescription. To learn more about illegal possession of drugs, you may visit the schedule of federally controlled substances.

Schedules: Which Drugs Can I Legally Possess?

The Controlled Substances Act of 1970 (CSA) classified controlled substances into five categories or schedules. Researchers or regulators added new substances like oxycodone, mescaline, and methadone over time. The list is updated annually, so check for the most updated schedules.

Schedule I

Schedule I substances have a high potential for abuse. There is no currently accepted medical use and a lack of acceptable safety data even when used under medical supervision. This category includes hallucinogens, cannabinoids, heroin, LSD, marijuana, peyote, and ecstasy.

Doctors prescribe some drugs, like medical marijuana and opiates. LSD is the subject of legitimate medical research. Some indigenous Americans have used peyote for millennia. Its use in religious ceremonies is federally protected. However, that protection does not exist under state law in many states. Federal law provides clarification of this protection.

Schedule II

Schedule II substances have a high potential for abuse, and usage can lead to severe psychological or physical dependence. These substances have a currently accepted medical use in the United States. Examples include Dilaudid, hydrocodone, Demerol, OxyContin, Percocet, morphine, fentanyl, codeine, and some amphetamines (ADHD medications, for example).

Schedule III

Schedule III substances may stimulate the central nervous system but have less potential for abuse than Schedule II drugs. Their use has a moderate to low potential for physical or psychological dependence. These drugs include 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 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. However, there could be a defense if a medical professional prescribed the drug and it was lawfully purchased.

Penalties for drug offenses — as mentioned previously — vary greatly, depending on:

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

Federal penalties are notably severe. A federal charge for possessing 500 to 4,999 grams of cocaine carries a five- to 40-year prison sentence and a fine of up to $5 million. Aggravating factors could result in a sentence of life imprisonment and higher fines. These factors include prior convictions, death, or serious injury. 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. The Supremacy Clause of the United States Constitution establishes this doctrine. The Controlled Substances Act is a federal law that applies regardless of state laws.

States can determine how they enforce or choose not to enforce drug laws. Some states have stricter laws than the federal government. Others have lower penalties and focus more on providing avenues for treating substance abuse 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 primarily chosen not to interfere with state marijuana policies. Marijuana possession remains technically illegal in all 50 states. And yet, most states allow the use of "medical marijuana" and cannabis products.

As of 2023, the sale and use of marijuana for recreational purposes is legal in 23 states, the District of Columbia, and several U.S. territories. Eight 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 an example of a state in the process of change. While marijuana is illegal, police in Austin are not charging people for possessing less than 4 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 or manufacture with the intent to 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? Can you legally travel with your prescription medication? It is best to talk to a criminal defense lawyer. They can give you a better understanding of your potential defenses and your rights.

Note that having a criminal record, particularly a drug conviction, may bring lifelong consequences. Thus, it is best to talk to a legal professional. A criminal defense attorney may also be helpful if you have faced drug-related charges.

FindLaw has a directory of criminal defense attorneys available in every state. The directory has a list of law offices and their contact details.

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