Created in 2003, the Terrorist Screening Database was intended to help the US track terrorists and prevent any further terror attacks in the US.

Despite the best intentions of the list, however, the system has proven to be confusing and flawed.

On numerous occassions, the watch list has failed to prevent attacks — Omar Mateen, who carried out a mass shooting at an Orlando nightclub, was previously on the list in 2013 but was removed after 10 months — or have failed at tracking potential terrorists, such as the failed 2009 underwear bomber.

On the other hand, it is incredibly easy for innocent suspects to be placed on the watch list with no warning. Whereas some obvious indicators will land someone on the list, such as carrying out a violent attack at an airport, other innocuous actions such as being an acquaintance of a suspect on the watch list can also lead to being watch-listed.

And being removed from the list can be as opaque as being placed on it. Most suspects on the list never know they’re technically under investigation.

 

Read the whole story from Business Insider.

Feature image courtesy of Reuters.