The private investigation into voting irregularities on the House floor last August is going public.

House Majority Leader Steny H. Hoyer is set to testify next Tuesday at the first public hearing on the matter since September, when the select committee tasked with investigating the episode issued a brief interim report.

The committee has arranged for testimony from Hoyer, D-Md.; House Parliamentarian John Sullivan; Rep. Michael R. McNulty, D-N.Y., who was in the Speaker’s chair at the time; and several staff members. All the witnesses have already been interviewed privately.

The hearing will air the sequence of events in the words of those involved in the decision to declare that Democrats had defeated a motion to recommit.

Rep. Bill Delahunt, D-Mass., chairman of the special panel, predicted the hearing would last an entire day.

Delahunt and his Republican counterpart, Rep. Mike Pence of Indiana, recently requested $150,000 to complete their work, which will include an extensive report with recommendations to change House rules.

Previously, the committee had been allocated $300,000.

Based on hours of staff interviews with all involved in the procedural drama, Pence predicted that the committee will recommend “dramatic changes” in the way the House governs its voting procedures.