The Controlled Substances Act: Overview

The federal Controlled Substances Act (CSA) regulates the manufacture, distribution, and possession of controlled substances such as hallucinogens, narcotics, depressants, and stimulants. 

Throughout much of the 20th century, the United States made many attempts to outlaw or regulate certain drugs. As a result, some 200 separate laws address controlled substances. In an attempt to remedy this, Congress passed and President Richard Nixon signed the Controlled Substances Act in 1970. A key goal of the act: combining all prior existing federal drug laws into one single statute.

What Does the Controlled Substances Act Do?

The act categorizes drugs into five classifications or “schedules." The schedules reflect each drug's medical use, potential for abuse, and status in international treaties. The CSA became law as Title II of the Comprehensive Drug Abuse Prevention and Control Act of 1970.

The CSA places all controlled substances into five schedules at 21 U.S.C., Section 812, labeling them with Roman numerals. Generally speaking, drugs included in Schedule I are the most regulated. They were deemed to have no medical value and high potential for abuse. The schedules descend from most dangerous to least dangerous. Thus, the drugs in Schedule V have low potential for substance abuse.

Repeated use of Schedule II substances can lead to psychological dependence and physical dependence. The opioid crisis of the 1990s and 2000s involved abuse of many drugs in this area. The over-prescribing of drugs like Vicodin and oxycodone led to lawsuits against a number of drug manufacturers and distributors. Demand for treatment remains a top concern of public health officials.

Narcotic drugs can appear throughout the schedules. They include opiates and opioids. An opiate is a natural derivative of opium poppies. An opioid is a similar drug that is either partially or wholly synthetic. Those with no accepted medical use, such as heroin, fall under Schedule I.

Some examples of drugs and their classifications:

  • Schedule I: Heroin, ecstasy (MDMA), LSD (lysergic acid diethylamide), peyote, psilocybin (magic mushrooms), and marijuana (cannabis). Efforts to move cannabis out of Schedule I remain ongoing. Limited studies are available, in large part due to its criminalization. The drug's recent legalization in several states may support the theory that it has achieved accepted medical use.
  • Schedule II: Amphetamines (Adderall), barbiturates, cocaine, methamphetamine, morphine, Vicodin, oxycodone, fentanyl, methadone, Phencyclidine (PCP) and Ritalin
  • Schedule III: Anabolic steroids, ketamine, testosterone, and Tylenol (ibuprofen) with codeine
  • Schedule IV: Ambien, Xanax, Klonopin, Ativan, and Valium
  • Schedule V: Lyrica and cough suppressants with codeine

Federal law prohibits the illegal possession, use, manufacture, or distribution of controlled substances. For the average citizen, possession of a controlled substance is a federal and/or state crime. The exception is if they have a valid prescription from a doctor.

The grouping of controlled substances makes it easier for legislators to draft or change rules covering multiple drugs at a time. Many states have borrowed or referenced the federal schedules' definitions in their own enactment of drug possession laws and other statutes.

Drug analogs — designer drugs meant to mimic controlled substances — are also covered by the CSA.

The penalties for illegal drug crimes may depend on the drug's schedule to some extent. In general, trafficking in a Schedule I controlled substance will carry stricter criminal penalties than a similar offense involving a substance in Schedule IV. However, marijuana and some other drugs have stand-alone penalty statutes that provide specific punishments. Most trafficking offenses will constitute felony drug crimes. Drug possession crimes may be felony or misdemeanor crimes based on the drug and the weight at issue. The weight of the drug involved can trigger mandatory minimum sentences in certain cases.

Congress has also enacted laws to address the use of precursor chemicals. In 2006, following the lead of similar state laws, federal legislation began regulating chemicals used in the production of controlled substances. The CSA identifies certain listed chemicals used or diverted into the illegal production of controlled substances.

List I chemicals are generally precursor reagents. List II chemicals are mainly solvents. The DEA can label certain chemicals as immediate precursors. This means that they provide the principal compound used in the manufacture of a controlled substance. If the DEA registers a chemical as an immediate precursor, it can place it under the schedule and not on a list.

A particular concern behind such regulations relates to methamphetamine. Meth is an illegal substance that can be crudely manufactured in people's basements or even vehicles. Common substances used in cough medications, such as ephedrine and pseudoephedrine, are part of the process.

The federal regulations set in place limitations on purchases of these over-the-counter medications. They also required identification and record-keeping of all sales by pharmacists. This information has aided law enforcement investigations into the illegal production of methamphetamine.

The Drug Enforcement Administration

The Controlled Substances Act mandates that every manufacturer, distributor, importer, or exporter of any drug must register with the government. Registrants are required to keep accurate records of their inventory and transactions. The Drug Enforcement Administration (DEA) can access such records during an investigation.

The DEA, created in 1973, is an agency of the federal government. It has the authority to regulate the use of controlled substances and enforce the law. It controls the process that sets where drugs fall on the schedule. It must consult with the federal Food and Drug Administration (FDA) and the Department of Health and Human Services (HHS). It can begin proceedings to add new prescription drugs to the federal schedules.

The DEA also ensures that registrants abide by security controls and storage requirements for lawful drugs. Finally, the agency works cooperatively with international, state, and local government partners in efforts to thwart drug trafficking and other crimes.

The Changing Status of Marijuana in the US

The mind-altering chemical in the controlled substance known as marijuana is delta-9-tetrahydrocannabinol (THC). Although marijuana is included in federal Schedule I, many states have legalized it for medical or recreational use. Because federal law takes precedence, the outcome of this conflict hinges on whether federal authorities choose to enforce the prohibition in the face of state opposition.

At present, the Biden administration has supported efforts to legalize personal use of marijuana. In a 2022 statement, President Joe Biden announced he would pardon all those convicted of federal crimes associated with simple marijuana possession. He urged state governors to take the same action. He also said he was directing the secretary of the Department of Health and Human Services and the attorney general to take steps to review the current placement of marijuana under Schedule I of the CSA.

To remove marijuana from Schedule I, Congress could amend the CSA and make that change itself. Absent congressional action, the DEA can take administrative action to make the change. The DEA, the FDA, or any interested party can start the process.

Yet before adjusting the location of the drug in the schedule, the FDA must approve the move. The FDA has never found acceptable medical use for marijuana in the past. Some 38 states have now legalized marijuana to some degree for medical use. It remains an open question whether that may influence the FDA evaluation in the future.

The Enforcement of Drug Crimes

Although the DEA takes the lead in setting drug policy in the U.S., federal law enforcement falls under the attorney general and the Department of Justice (DOJ). Investigations of federal drug crimes can occur through several agencies. These include the DEA, the Federal Bureau of Investigation (FBI), and the Bureau of Alcohol, Tobacco, and Firearms (ATF). Investigations into illegal drugs can also occur through cooperation with other agencies. For example, the DEA can work with Immigration and Customs Enforcement (ICE) and the Border Patrol.

The actual prosecution of drug crimes falls to federal prosecutors from DOJ who work in U.S. attorney's offices across the country. Key federal statutes that may appear in criminal cases include:

  • 21 U.S.C., Section 841 (prohibited acts): Bans anyone from manufacturing, distributing, dispensing, or possessing with intent to manufacture, distribute, or dispense a controlled substance or a counterfeit controlled substance. Sets penalties for federal prison sentences and fines based on the type of drug and the amount involved
  • 21 U.S.C., Section 844 (penalties for simple possession): Bans possession of a controlled substance without a proper prescription. Sets penalties based on schedule and amount of drug
  • 21 U.S.C., Section 863 (drug paraphernalia): Bans sale of drug paraphernalia and use of U.S. mail or interstate commerce to transport it. Provides for seizure and forfeiture of items. Provides exemptions for authorized producers and items used for tobacco products
  • 21 U.S.C., Section 960 (prohibited acts): Bans the import and export of illegal drugs

In 2020, the United States Sentencing Commission reported on sentencing of more than 64,000 federal criminal offenses. Drug offenses were 26.1% of all criminal cases. The majority of federal drug prosecutions that went to sentencing related to trafficking and distribution (16,829). A minority of cases involved simple possession (439). Methamphetamine was the most common drug in the caseload.State and local law enforcement agencies investigate and prosecute the vast majority of drug crimes in the United States today. According to the FBI, there are more than 1 million arrests related to illegal drugs each year.

Facing Drug Possession Charges? An Attorney Can Help

Criminal charges under the Controlled Substances Act or state law can have significant consequences. A criminal record may follow you for a lifetime. You should consider what defenses or options may be available to you. An experienced criminal defense lawyer who knows drug laws can advise you about your specific situation. Consider talking with a qualified criminal defense attorney near you today for personalized legal advice.

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