Psychotropic drugs and crime

DEFINITION: Broad group of substances that are capable of affecting human minds and behavior.

SIGNIFICANCE: Forensic scientists are often called upon to determine whether psychotropic drugs are present in persons or at crime scenes and the exact nature of any such substances found.

Psychotropic drugs are also known as psychoactive substances. They include licit and illicit drugs as well as plants, foods, and household products not commonly thought of as drugs or drug-like. Because of this breadth of forms, the potential range of effects of these substances is very broad. In general, however, psychoactive drugs have primary action on the central nervous system (brain and spinal cord) and the behaviors and reactions it controls. These include processes such as attention, awareness, physical and other perceptions and feelings, emotions, concentration, learning, judgment, and thinking.

Drugs that are considered psychoactive are generally classified into groups based on the conditions they are legally used to treat and how they affect the body. Some common groupings include analgesics, antidepressants, antiepileptics, antiparkinsonian drugs, antipsychotics, anxiolytics, central stimulants, general depressants, psychedelics, sedative-hypnotics, and tranquilizers. Substances of abuse can be classified into many of these categories as well; however, for diagnostic purposes, they are considered separately. Substances of abuse include alcohol, amphetamines, caffeine, cannabis (or marijuana), cocaine, hallucinogens (some of which are used as club drugs), inhalants, nicotine, opioids, phencyclidine (known as PCP), sedative-hypnotics, and anxiolytics.

Caffeine, hallucinogens, and inhalants illustrate the fact that psychotropic substances are not always found in pills or other common medicinal forms. Caffeine is found in many everyday food items, including coffee, tea, and chocolate. Hallucinogens may be found in plants and fungi. Inhalants are found in household and workplace substances, such as gasoline, glue, lighter fluid, liquid correction fluid, paint, paint thinner, and varnish, as well as in the forms of amyl and butyl nitrate, general anesthetics, and nitrous oxide.

Common Uses

Psychotropic drugs have many positive uses. Various types of these substances are used in the treatment of mental illnesses such as attention deficit hyperactivity disorder (ADHD), depression, bipolar disorder, and schizophrenia. Antidepressants and mood-stabilizing drugs such as lithium are good examples of the psychoactive substances used for these purposes. Analgesics, including morphine, are used to treat pain. Other psychotropic drugs that are used to treat some complex conditions, such as epilepsy, have direct effects on the conditions they are used to treat as well as side effects that affect the mind.

Psychotropic drugs are also used recreationally and abused, but it is not just illicit recreational drugs that are of forensic interest. The most commonly used licit drugs—alcohol, caffeine, nicotine, and prescription drugs, including opioids—are also of interest to law enforcement. Alcohol, for instance, has long been related to crime; forensic scientists are often involved in determining the presence and amounts of alcohol in the blood in cases of persons accused of driving under the influence, public intoxication, and underage drinking. Caffeine intoxication may cause agitation, which in certain circumstances could contribute to behavioral disturbances, such as aggressive driving or verbal assault. Forensic scientists may conduct examinations of nicotine for cases related to accusations of smoking in restricted areas, such as on airplanes, investigating suspected nicotine poisoning, or for lawsuits related to health damages caused by nicotine. Psychotropic drugs that are available by prescription, such as oxycodone, are often linked to crimes involving prescription forgery or improper prescribing of these substances by physicians.

Continuing Controversies

In the United States, a number of controversies surround psychotropic drugs and their effects. These include long-running debates about the regulations attached to the production of these substances, as well as the laws concerning the distribution of such drugs and access to them. The characteristics of the users themselves also spark controversy. Although many psychotropic substances have been shown to be valuable in addressing suffering, debates persist about “good” and “bad” drugs, and the context of use is often ignored. Fierce disagreements have arisen regarding why, how, and when research on the value of any drug should be revisited.

Debates among lawmakers relate to the substances that should be regulated, by what means, and to what extent. The process from drug production to end users is a long chain of events, and insufficiencies at any point can cause problems for those involved in the chain, costing them money. Decision making around the regulation of psychotropic drugs thus receives great scrutiny, because a delicate balance must be maintained in assigning who—producers, distributors, dispensers, users, the public at large—should pay the costs associated with any one drug and its impacts.

Many of the concerns about the users of psychotropic drugs tend to center on recreational users, focusing on how they should be controlled, cured, or prosecuted. Some argue that users of these substances have certain moral or ethical weaknesses, but given that the use of psychoactive drugs, in one form or another, is the norm, this argument is ill founded.

Another issue is the nonuse of these substances by individuals who might benefit from them under medical care and thus indirectly benefit society. Not all persons who might need psychotropic drugs are willing to take them, and some might take them only in certain circumstances if they are able to make such judgments at all. If their refusal to use these substances will endanger their safety or the safety of others, should these persons be forced to take the drugs? Such matters are relevant to law enforcement in that they involve the delicate balance between honoring hard-won civil liberties and protecting individuals and society from harm.

Outcomes of Use

In the early twenty-first century, novel psychoactive substances (NPS) emerged. These substances include hallucinogens, opioids, and synthetic cannabinoids. Their use has resulted in negative outcomes, including injury and death. The US Drug Enforcement Administration, in 2025, highlighted nitazenes, synthetic opioids similar to fentanyl, as an emerging threat. Researchers have reported users experiencing overdose fatalities and clinical treatment and hospitalization. Arrests have been made for driving under the influence of drugs.

Bibliography

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“Central Nervous System (CNS).” Cleveland Clinic, 12 Nov. 2023, my.clevelandclinic.org/health/body/central-nervous-system-cns. Accessed 26 Feb. 2026.