The former leader of Sinn Fein, formerly the IRA's political wing and now the largest party in the Northern Irish Assembly, is fighting a civil lawsuit which aims to hold him liable for three bombings in Britain in the 1970s and 1990s.
Adams has long faced accusations that he was a member of the Provisional IRA, including from former members of the paramilitary group, which he has always denied.
The 77-year-old entered the witness box on Tuesday and wished "a very happy St Patrick's Day" to the judge, before he was questioned by his lawyer Edward Craven about how he joined Sinn Fein in 1964, when it was banned.
He is being sued by three people injured in three bombings: one at London's Old Bailey court in 1973, the PIRA's first on the British mainland, and two 1996 blasts, targeting London's Docklands and Manchester. They are seeking a finding on the balance of probabilities that Adams is personally liable as a senior member of the PIRA.
But Adams said in his written witness statement: "I was never a member of the IRA or its Army Council. ... I have never held any rank or role within the IRA, including on the IRA's Army Council.
"I have never held a 'command-and-control role' in the IRA and have never been a senior, let alone most senior figure, in the IRA."
Adams became Sinn Fein leader in 1983, establishing himself as the best-known face of the movement seeking to end British rule in Northern Ireland.
