This is unlocked by completing four weekly contracts for any combination of the above factions. To access pursuits, bring up the Start menu, hold down , and choose Goals in the 1/2 o'clock position. From there, tab over to Contracts using or . Contracts typically involve killing specific enemies in certain locations to collect items. Weekly contracts usually take more time to complete.
Weekly contacts will become available after you reach 175 EGO and change every Monday. There is a 2-day weekend weekly added on Friday that lasts until Monday.
A great contracts resource: http://www.etaew.net/defiance/index.php