On 20 April 2015 the web site Instant Checkmate published a blog post claiming that the Federal Bureau of Investigation (FBI) had released a ranking that correlated the likelihood of criminal activity to zodiac signs:
According to the FBI, some astrological signs are more likely to commit crimes than others. So, we counted down through the dark side of the zodiac! Discover all the deadly traits of your astrological sign! Did you know you can find the horoscope (and criminal record) of almost anybody on Instant Checkmate? Give it a spin. You might be horo-fied to see the results!
Of particular note is the fact that Instant Checkmate is not in any way a news outlet, and their blog serves purely to convert site visits into sales of the company's disreputable "background check" services. The excerpt from their blog quoted above was the only portion that mentioned the FBI at all, and the article provided no links to any such "release" by the FBI. Moreover, the company's blog is deceptively styled to look like a separate crime-related blog to disguise its purpose as a funnel to drive sales of Instant Checkmate's poorly-rated services.
The likewise unreliable gossip site Mediatakeout.com published a similar article that cited another item from a service-selling web site as its source of its claims, a 10 August 2010 blog post from Insightful Psychics. However, the psychic web site did not claim that their ranking of criminal activity by zodiac sign stemmed from any study undertaken by the FBI; rather, the company merely used birthdate and crime information compiled by the FBI to deduce that persons born under certain zodiac signs were arrested more frequently than others:
Based on the information from the Federal Bureau of Investigations (fbi.gov), Cancer are the most arrested criminals, which shows they are one of the more dangerous signs in the zodiac circle. After Cancer, Taurus is the ones that commit the most crimes. Both signs don’t have much but they’re quite temperamental. Sagittarius is listed as number three.
It would probably be the case that one of the 12 astrological signs would be more "likely" to commit crimes than the other 11 (even if by a statistically insignificant margin), but there is no compelling evidence that arbitrary birthdates have a causal correlation with criminal tendencies (any more than, say, the initial letter of one's surname does). Such correlations are often used to create the illusion of causation, however, and in the cases of Instant Checkmate and Insightful Psychics, those random inferences were arranged to create a sense of urgency with respect to need for background checking or psychic services.
Nevertheless, we contacted the FBI to determine whether any such research had ever been undertaken by that agency concerning zodiac signs and criminality. The Bureau informed us that all information of that nature was freely available on their web site, a search of which returned content related only to investigations relating to the Zodiac killer and files that included the brand name "Zodiac."
In a 23 June 2016 e-mailed reply, a FBI representative stated:
We have contacted the FBI’s Behavioral Analysis Units and were unable to find any record/information confirming any study of zodiac signs of killers/serial killers contributing to higher rates of criminality.