Sexual Offenders

A Look Into A Typical Sexual Offender

By : Catherine Sauer

Sex Offenders Walk Among Us

Not all sexual offenders are in jail. How often do you think about sex offenders around you? Do you drive past sex offenders on the interstate, walk past sex offenders in the grocery store?

A sex offender is an individual that has been convicted of a sexual crime. Sexual crimes include sexual assault, sexual abuse, rape, sodomy, kidnapping, child molestation, sexual misconduct, sexual exploitation, possession of child pornography, and indecent exposure. As the severity of crimes varies, it is not reasonable in our justice system to keep all sex offenders incarcerated for the rest of their lives.

After convicted sex offenders complete their sentence, they are allowed to reintegrate back into society with restrictions on their liberties. One of those restrictions is that the convicted sex offender must officially register as a sex offender. This requirement can be for 15 years, 25 years, or for their remaining lifetime. As convicted sex offenders continue their lives outside of incarceration, they are still presented with limitations to their liberties. For example, convicted sex offenders cannot live within 1,000 feet of a public or private school, be physically present within 500 feet of a public park with playground equipment or a public swimming pool, or serve as an athletic coach, manager, or trainer for any sports team in which a child younger than 17 is a member. For more information on Missouri’s laws, please visit the Missouri State Highway Patrol’s factsheet on sexual offenders.

Convicted sex offenders may be present in your community, but the observations made here are not intended to persuade you to act any differently towards them. But in the interest of data science, how much do sexual offenders blend in?

The age of registered sexual offenders living in MO, either in or out of jail, should be pretty evenly distributed. Younger sexually active individuals would be more likely to be convicted of a sex crime. As registered sex offenders age, they become less sexually active, they are removed from the sex offender registry, or they pass away, so the number of aged sex offenders is fewer in number. This is what the elementary bell curve shows us here.

Would it be reasonable to assume that younger individuals who are more sexually active are more likely to commit their first sexual offense?

You can almost see that the graph is skewed such that individuals commit their first sexual offense when they are younger. This would be easier to see if the outlier was removed.

Let’s look at that pretty extreme outlier.

individual_offense.loc[individual_offense['Charge Counts'] > 30].iloc[0]['Charge Counts']
df_offender.loc[df_offender['Name'] == individual_offense.loc[individual_offense['Charge Counts'] > 30].iloc[0]['Name']]['Offense'].unique()

This sexual offender representing the outlier was convicted of 55 counts of either Possession of Child Pornography or Possession with Intent to Promote Child Pornography.

Let’s exclude the extreme outlier.

	individual_offense[individual_offense['Name'] == individual_offense.loc[individual_offense['Charge Counts'] > 30].iloc[0]['Name']].index, 

The elementary bell curve can be seen much clearer now.

As one would expect, the younger, more sexually active population is more likely to be a registered sex offender.

How do registered sex offenders blend in with society on the road? Do registered sex offenders tend to own Ford vehicles? Chevrolet? Fiat?

For the sake of this blog post, let’s focus on the vehicle ownership of registered sex offenders in MO charged with child pornography and rape, respectively. Please remember that income varies for all registered sex offenders and this may be affecting the popularity of vehicle manufacturers.

However, this data is not very useful. A lot of our vehicles are manufactured by Ford or Chevrolet. Let’s consider the popularity of vehicle manufacturers.

When normalizing the data, it appears that more registered sex offenders own Chrysler manufactured vehicles than expected.

If you would like to access the MO sex offender registry, please visit the Missouri State Highway Patrol’s factsheet on sexual offenders. To access the vehicle manufacturer data used in this analysis, please navigate to If you are a victim of sexual assault and seek suppport, please visit the National Sexual Violence Resource Center or call 800.656.HOPE.