Adolescents, the Law, and the "Maturity Gap"

Developmental science offers guidelines to courts about adolescent capabilities.

Posted Mar 01, 2019

Teen Gangster
Source: pixeltweaks/Pixabay

This is the first of a two-part series about the maturity gap.

Are 16-year-old girls mature enough to decide whether to obtain an abortion without input from their parents? In 1990, the American Psychological Association said "yes" in its amicus brief to the U.S. Supreme Court in Hodgson v. Minnesota.

Are 16-year-old boys and girls who have been convicted of murder less blameworthy than adults because of their developmental immaturity? In 2005, the American Psychological Association said "yes" in its amicus brief to the U.S. Supreme Court in Roper v. Simmons.

At first blush, the APA's opinions in these two cases appear to contradict themselves. In Hodgson, the experts argued that 16-year-old girls are mature enough to make an adult-like decision about an important matter. In Roper, the experts argued that 16-year-old girls (and boys) should never be sentenced to death because they are "developmentally immature" and not yet able to make adult-like decisions.

Did APA's experts spin the science merely for the sake of youth advocacy? Probably not. Their contrasting opinions in these cases actually make good sense once one understands the relevant developmental science.

The findings of empirical studies by developmental psychologists consistently point to different yet complementary conclusions.

  1. On tests that measure logical reasoning and fluid intelligence (the ability to analyze and solve problems), 16-year-old children typically perform as well as adults.
  2. On tests that measure impulse control, self-regulation, and resistance to peer pressure, 16-year-old children typically perform less well than adults.

The fact that cognitive maturity (CM) develops earlier and peaks sooner than emotional maturity (EM) is called the "maturity gap." The size of the gap is substantial—CM levels off for most people around age 16, but EM doesn't level off until age 25 or 30.

The existence of a maturity gap has interesting implications for legislators and judges. If a particular decision requires adult-like reasoning skills, then it makes sense to allow 16-year-olds to make that decision for themselves because, on average, they reason as well as adults. Examples include many medical decisions (whether to obtain an abortion) and legal decisions (whether to accept a plea bargain).

If a particular decision requires adult-like emotional maturity, then it makes sense to punish juvenile offenders less harshly because they aren't fully developed in terms of their ability to resist peer pressure, avoid risky situations, control their impulses, and manage their emotions. Examples include acts that are often committed in groups (reckless driving), acts that are seldom premeditated (aggravated assault), and acts that occur "in the heat of the moment" (unprotected sex).

To be clear, developmental psychologists don't believe that juveniles should not be held responsible for their bad behavior. The issue is one of degree. Persons who have diminished capacities should not be held fully responsible for their poor choices.

A maturity-gap approach can lead to some non-intuitive judgments. For example, suppose a 16-year-old girl freely chooses to move to the big city and become a sex worker at a massage parlor. If the girl is arrested and convicted of prostitution, should she be punished as severely as a 30-year-old sex worker?

According to the maturity-gap approach, the answer is yes. By age 16, the typical adolescent's cognitive and reasoning capacities are basically indistinguishable from those of the typical adult--and freely choosing to work in the sex industry is not the kind of decision that is made in the heat of the moment or under pressure from one's friends. Therefore, a 16-year-old should be treated like an adult in this kind of situation.

There may be other reasons for thinking a 16-year-old should be treated less harshly than an adult in this situation, but those reasons presumably rely on something other than scientific studies of developmental maturity.

The second post in this series examines the universality of the maturity gap.


Steinberg, L., Cauffman, E., Woolard, J., Graham, S., & Banich, M. (2009). Are adolescents less mature than adults?: Minors' access to abortion, the juvenile death penalty, and the alleged APA "flip-flop." American Psychologist, 64, 583-594.