Charles Logan was Vice President of the United States during the administration of President John Keeler. He became President pursuant to the 25th Amendment after Keeler was grievously wounded when Air Force One crashed during Day 4.

Beholden to a highly secretive corporate cabal inside BXJ Technologies, President Logan sponsored the Sentox nerve gas conspiracy with the intent to acquire more oil for America from Central Asia. Among the actions he supported was the selling of Sentox nerve gas to terrorists and the assassination of Former President David Palmer. When former CTU agent Jack Bauer discovered and neutralized Logan's lower-level conspirators during Day 5, the President himself took the reigns and attempted to direct the entire apparatus of the government and the military to cover up his crimes. However, Bauer and several others—including the First Lady herself, Martha Logan—exposed him to the Attorney General, and he was quietly removed from office.

Charles Logan served a lengthy house arrest sentence, and the full truth about his crimes was not revealed to the public. After a failed attempt to legitimately rehabilitate himself morally—and a close call with death during Day 6—Logan received a pardon from President Noah Daniels and returned to civilian life. On Day 8, upon learning of Kamistani President Omar Hassan's assassination and Russia's threats of withdrawing from the planned peace accords, he offered his assistance to President Allison Taylor, correctly calculating that he could use his leverage to coerce Yuri Suvarov into signing. When Taylor realized that her partnership with Logan had destroyed her integrity near the end of Day 8, she scuttled the peace treaty. In despair, but also in an attempt to guarantee the murder of Jack Bauer, Logan attempted suicide by a gunshot to the head.