The Council of Daves is the name used to refer to the leaders of DedSec, and they are also referred to occasion as simply 'The Daves'.
They are mentioned throughout the main Watch Dogs storyline but they become more involved in the story in the Bad Blood DLC.
The members of The Council of Daves are referred to with social media-esqe names by the profiler. Their real identity is unknown. However, it is known that Defalt attempted to become a Dave with the assistance of Badboy17 (Clara Lille), as revealed in the DLC Bad Blood 'The Council of Daves' side investigation. Footage of Defalt and Clara waiting together and being confronted by the Daves is shown when scanning a QR code in Pawnee. Defalt becomes angered when Dedsec denies him membership due to his lack of anonymity due to his DJ career.