Derrick Yates

Derek Yates was a British computer hacker who was responsible for hacking a drone used by the American military and killing several soldiers by means of friendly fire. Yates had also been in possession of a "package", which he intended to sell to Margot Al-Harazi.

Before Live Another Day
Yates had previously been working for Adrian Cross, the leader of a hacker organization but was let go because of his greed, selling data to the highest bidder and hacking into military weapons systems.

Live Another Day
In the last few minutes before 12:00pm, Yates is revealed to have been the one responsible for hacking the military drone that dropped missiles, killing several soldiers in an act of supposed friendly fire. Yates calls his conspirator, telling them "it is done." (Day 9: 11:00am-12:00pm)

The conspirator, Margot Al-Harazi, calls him, impressed with his work of hacking the drone and they arrange a meeting place for the package in his possession, where she will give him the money. Yates and his Russian girlfriend, Simone, are forced to flee when Jack Bauer tracks him down at his drug dealer Basher's house. At the meeting place, Yates considers double-crossing Margot. Yates goes to the bathroom and Simone follows him in. Behind his back, she pulls out a knife, stabbing him through the side of the head and killing him instantly. Unbeknownst to Yates, Simone was actually the daughter of his conspirator, who had been posing as a Russian in order to get the device.