Sheldon's Criminal "Build" Theory
William Sheldon developed a biological theory of criminality based on body types called somatotypes. He proposed that certain body shapes were more prone to criminal behavior.
Sheldon's somatotypes:
- Ectomorphic - thin and fragile
- Endomorphic - round and soft
- Mesomorphic - muscular and triangular
Definition: Somatotype - The structure or build of a person's body
Sheldon argued mesomorphs were most associated with crime due to their intimidating appearance and tendency for risk-taking behavior.
Research methods:
- Photographed college students (control) and delinquents
- Rated subjects on a 1-7 scale of resemblance to mesomorphs
- Studied front, side and back views of 4000 men
Example: Sheldon was inspired by observing his father breed poultry and dogs, noting genetic influences
Evaluation:
Strengths:
- Some studies found small associations between body type and criminality
- Used control groups for comparison
- Large sample size of 4000 subjects
Highlight: Glueck and Glueck (1956) found 60% of offenders were mesomorphs vs 31% of non-offenders
Weaknesses:
- Social class could be the true cause, not body type
- Ectomorphs and endomorphs also commit crimes
- Body types are not fixed for life
- Correlation does not prove causation
- May lead to self-fulfilling prophecy for mesomorphs
Quote: "Glueck and Glueck (1950s) found that criminality was best explained by a combination of biological, psychological and environmental factors."





