(CNN) House Judiciary Chairman Jerry Nadler is poised to hold a committee vote Wednesday to allow staff members to question Attorney General Bill Barr during a Thursday hearing. Barr has said he will not attend the hearing if the House Judiciary sticks to this new proposed format.

Allowing staff members -- in addition to lawmakers -- to question Barr, if the committee votes to permit it, wouldn't violate any rules but Republicans have argued the move is without precedent.

Nadler's office has cited several instances where congressional staff were allowed to question witnesses.

Facts first: The narrow question of determining "precedent" depends on how you define it, but CNN could not locate an instance where a Cabinet official was interviewed by staff members during a public hearing before the House Judiciary Committee. However, there have been instances where staff attorneys were permitted to interview witnesses. And ultimately this argument may have only political importance.

Nadler's office cited several instances to support the idea that allowing staff to question Barr would not go against precedent, including public and private hearings.

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