Story highlights Sen. John McCain has been one of President Donald Trump's most vocal Republican critics

Asked what he wants to hear from James Comey, McCain said, 'Whatever he wants to tell us'

(CNN) One particularly vocal senator will get a chance to question former FBI Director Jim Comey on Thursday thanks to quirky Senate rules: Sen. John McCain.

The Arizona Republican, who is not a full member of the Senate intelligence committee, confirmed to CNN Tuesday that he plans to attend the hearing and question the former FBI director who was fired by President Donald Trump last month.

McCain is able to appear at the hearing because he is chairman of the Senate Armed Services Committee. As Armed Services chairman, he is also an "ex officio" member of the Intelligence Committee, which means he doesn't get to vote but does get to attend meetings and hearings, including this one.

McCain, of course, has been at times one of Trump's most vocal Republican critics, and has compared the Russia scandal to Watergate.

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