Tanner was complicit with the Jacobs administration for rushing the development of a hybrid fighter that killed Steven Hiller in the 2007 ESD Spring Expo. Prior to the incident, ESD scientist David Levinson warned Tanner about his concerns about the hybrid in which Tanner disregarded his warnings and had him removed from the hybrid project. Much to Tanner's reluctance, Levinson was appointed as the new ESD Director.
When Rhea Base was destroyed, Collins attempted to contact Lanford, but Tanner said that she would be available after the press tour. Levinson told Collins to bypass Tanner in any way to reach the President.
During the upcoming 20th anniversary of the War of 1996, an unknown alien spaceship appeared on the Moon. Tanner was very vocal to implore President Lanford to deem the ship as a threat, despite Levinson's concerns that it was unrelated to the aliens from the War of 1996. Lanford eventually conceded to giving permission to the ESD to destroy the vessel. Levinson then proposed to send a team to investigate the debris, but Tanner dismissed it, saying that there were no life signs, and ordered him back to Washington, D.C. Levinson, however, hanged up on Tanner.
Tanner participated in the anniversary in Washington and was witnessed to the arrival of the Harvester Mothership. He and along with Lanford's Cabinet evacuated to the Cheyenne Mountain Complex before the mothership devastated the American east coast. After a failed counterattack against the Harvesters, the aliens assaulted Cheyenne and Tanner was among those killed.