1. Do Identical Twins Share Similar
Criminal Behaviors
Maria L Guy
Argosy University

2. Introduction
Identical twins = Monozygotic
Resulting from a single egg fertilized by a single
sperm cell then splitting into two identical
fetuses.
Such twins share identical DNA, are always the
same sex and blood type (twin-pregnancy-
and-beyond.com, 2011).

3. With so much shared DNA data, the possibility
for shared criminal behaviors I propose to be
relatively high.
I believe there would be a high correlation of
crime activity between the two identical
twins.

4. Rushton, J. P., Fulker, D. W., Neale, M. C., Nias, D.
K. B., & Eysenck, H. J. (1986) found that
60% of was altruism, empathy, nurturance,
aggressiveness, and assertiveness was
attributed to genetics and virtually 0% was due
to the twin’s common environment.
Rowe (1985) further reinforced the findings
above as his study of teenage twin youths
found that
61% of female twins engaged in one or more
delinquent acts; and
71% of male twins engaged in one or more
delinquent acts.

5. Plimmer (2004) studied the Krays twin’s case which
indicates that before their crimes the Krays’ twins
were “showing signs of what kind of lives they
were prepared to live” (Plimmer, pg. 24, 2004).
From an early age these twins, as I propose that
most twins, show a deviation of behavior towards
criminality, which is not necessarily due to their
environment, but due to their shared genetics.
Murphy (1997) studied criminal twins through the
works of Charlotte Haldane whom stated, “Taking
the record of any criminal, we could predict the
behavior of a monozygotic twin placed in the
same environment. Crime is destiny” (Murphy,
1997).

6. Opposite direction
Not all of these twins have hereditability for
criminology; the opposite is true as well.
Rees (1994) wrote a piece on Mike and Mitch
Wilson who are monozygotic twins who share
a love for police work. Rees (1994) stated that
the twins “have so many similarities, it’s hard
to tell the two apart even for people who
know them best.”

7. Conclusion
The prevailing argument of my literature review is
that there is a connection between identical
twins, where if one has criminality qualities the
other twin will also have a level of criminality due
to their shared DNA. The literature also set a part
the sexes of the twins, male twins are more
prevalent towards violence and criminality where
females are not. Although the literature review
found that environment might play a small role in
criminality behaviors, the dominant factor for
criminality remains to be the shared DNA.

8. The research of twin studies has been around for a
long time, just as criminality has been. In today’s
environment, criminality is more of a problem
than ever. Walmsley (2005) reports that the
United States has the highest prison population in
the world, therefore it is vital for researchers to
be focusing on where criminology stems from
whether it be hereditary, environmental or both.
Furthermore, by searching for and discovering
the exact factors of criminology then there can be
a solution for the overcrowded prisons. Such a
discovery could change the world by opening a
new era of relatively crime free living.

9. References
Plimmer, J. (2004, Mar 07). THE KRAYS twins who ruled the east end through sick
violence; serial killers, cold-blooded murderers and gun-toting gangsters.. Sunday
Mercury, pp. 24-24. Retrieved from
http://search.proquest.com/docview/322262456?accountid=34899
Murphey, D. (1997). Crime as destiny: A study of criminal twins. The Journal of Social,
Political, and Economic Studies, 22(2), 254-254. Retrieved from
http://search.proquest.com/docview/216810026?accountid=34899
LAURI REES,- East Oregonian. (1994, Nov 09). Twins have criminals seeing double. The
Oregonian, pp. B.15-B15. Retrieved from
http://search.proquest.com/docview/416842336?accountid=34899
Rushton, J. P., Fulker, D. W., Neale, M. C., Nias, D. K. B., & Eysenck, H. J. (1986).
Altruism and aggression: The heritability of individual differences. Journal of
Personality and Social Psychology, 50(6), 1192-1198. doi:10.1037/0022-
3514.50.6.1192
ROWE, D. C. (1985), SIBLING INTERACTION AND SELFREPORTED DELINQUENT
BEHAVIOR: A STUDY OF 265 TWIN PAIRS. Criminology, 23: 223–240.
doi: 10.1111/j.1745-9125.1985.tb00335.x
Walmsley, R. (2005). World Prison Population List. King's College London: International
Centre for Prison Studies , 1-6.