|Affiliation:||United States government|
|Profession:||Secretary of Homeland Security|
|Played by:||Michael Cavanaugh|
|First episode:||"Day 3: 2:00am-3:00am"|
|Last episode:||"Day 3: 12:00pm-1:00pm"|
O'Laughlin was present in a staff meeting with President David Palmer via a live video feed. After Brad Hammond stated the resurgence of the Cordilla virus threat, O'Laughlin supported the idea of going public with the news to prepare as many Americans as possible.
O'Laughlin arrived to meet President Palmer personally, and advised him to ground all flights and severely limit transportation around the country to contain the threat. He argued loudly with Chief of Staff Wayne Palmer about this plan. Ultimately, the President chose to follow O'Laughlin's advice over Wayne's.