The head of the FBI says dramatic videos of police shootings are skewing public perception.

FOX's Rachel Sutherland reports from Washington:

Speaking to police chiefs in San Diego, FBI director James Comey said videos of deadly police encounters are feeding the idea that "something terrible is being done by the police" and that a lack of data on police shootings is leading people to believe that "biased police are killing black men at epidemic rates".

Comey recently announced the FBI is building a database to track deadly police-involved incidents. It should be up and running within two years.

In Washington, Rachel Sutherland, FOX News.

Follow Rachel Sutherland on Twitter: @SutherlandFOX