DNA and the Cops

Lately it seems news reports are full of stories about criminals who have been identified and arrested by use of Genealogy DNA.   I want to address some fears and explain how these law enforcement investigations really work.

April 24, 2018 was a huge day for Law Enforcement and for Genealogy Researchers using DNA.   That was the day the Golden Gate Killer was arrested and how he was caught sent shock waves around the world.  After a rape and killing spree that started in 1976 (over 50 rapes and over 12 murders), law enforcement had finally “cracked the case” by using a simple Genealogy DNA Database.

Suddenly everyone was wondering if all our DNA goes to the cops everytime we take a Genealogy DNA Test?   Conspiracy Theorists were screaming: “See!!!  We told you the Cops and the Government were collecting your DNA!!”   The reality is:  NO!  Cops and the Government are not collecting your DNA!!

The Allred DNA Project uses Family Tree DNA (https://www.familytreedna.com/) for our DNA testing.   Our DNA Project Manager, John Allred and I received an email letter from the CEO and Founder of Family Tree DNA a few weeks ago.  In this letter, Bennett Greenspan stated:


They cannot search or “dig through” FTDNA profiles any more than an ordinary user can.   As with all other genetic genealogy services, law enforcement must provide valid legal process, such as a subpoena or search warrant to receive any information beyond that which any other user can access. 

Ancestry.com and other genealogy DNA companies have issued similar statements.  In truth, when you purchase a genealogy DNA kit, you receive a lot of written information about the testing process.  You are told your DNA results are confidential and you are the only person allowed to see those results – unless you give others your password and permission to view the results.   No one – not even law enforcement – can see your DNA results unless you give them permission.   The exception is when a subpoena or search warrant is presented – and in that case, a judge has been shown proof that there is strong evidence that you have committed a crime.   So yes, if you are a criminal and law enforcement has collected enough evidence to prove you are a criminal and shows this to a judge who agrees, then yes, a subpoena might be issued.

However, if you are not a criminal – you have no worries.  No one can see your DNA results unless you give permission.

How was the Golden Gate Killer caught?  Yes, it was using Genealogical DNA – but he NEVER took a Genealogy DNA test.   So how did they catch him using DNA?

Last night I watched HLN’s series Unmasking A Killer.  (Excellent TV show although the numerous commercials were extremely annoying.)   They did a great job explaining how Genealogical DNA was used to catch him.

GEDMatch (www.gedmatch.com) is an online database that allows anyone to compare their DNA results with other participants.   Once you take a DNA test and receive your results, you can upload your DNA results to GEDMatch and receive information about how many people share similar DNA and how they may be related to you.  Depending on which DNA test you took, you DNA can be sorted to show people related to you via a common ancestor.  For example, you can find out how many people are related to you within a range that includes 4-5 generations.   This is valuable if you have hit that genealogy brick wall.

In the case of the Golden State Killer, a detective decided to give it a try.  The Killer’s DNA had been collected at the crime scenes but had not shown a match using Law Enforcement databases.  So the detective ordered a Genealogy DNA test kit, inserted the Killer’s DNA and sent it off for testing.  Once the results came back, they were uploaded to GEDMatch.  GEDMatch compared the results to other participants and produced a report that showed a number of matches to the Killer.  This is when Genealogists who specialized in analyzing Genealogical DNA went to work with the detective.  They had to do good-old-fashioned-genealogy to figure out who the common ancestor was – then figure out who all the descendants of that common ancestor were – then the detective and his team began the painstaking process of eliminating all of those descendants until they found the ONE – the Killer.

So NO – the DNA testing company did not allow law enforcement to search their database.  NO – law enforcement and/or the government is NOT allowed to see your DNA test results – UNLESS you upload your DNA to a company like GEDMatch.  YOU have to decide to upload your results.   No one forces you to upload your results – it is your choice and it is a valuable tool for genealogy research.  By uploading your results – you are giving others permission to view your results.

Genealogical DNA is a wonderful tool and I hope it is continued to be used to solve our genealogy questions.  Bottom line – your DNA results are private unless you choose to upload them to a company like GEDMatch.

To learn more about how Genealogical DNA was used to catch the Golden State Killer, watch the HLN series and/or go to: