Garda Commissioner Noirin O'Sullivan is to appear before an Oireachtas committee on Friday morning to answer questions about policing outside Leinster House.
The Committee for Procedures and Privileges (CPP) meeting is set to take place behind closed doors and follows clashes between anti-water charge protesters and gardaí outside Leinster House on Wednesday.
One Garda member was knocked out and hospitalised when a large traffic cone was thrown at members of the force and hit her on the head.
Garda sources said she was taken from the scene by ambulance and spent the night in hospital before being discharged on Thursday. She was expected to be on sick leave for a period as she sustained a head injury in the attack.
Two male protesters were arrested, one of whom was taken to Pearse Street station and the other to Kevin Street in the south inner city.
They were charged with public order offences and released to appear before the courts at a later date.
A Garda Inspector has been appointed to head an investigation team that will study video footage taken during the incident. Gardaí believe the footage will help to identify and bring about prosecutions of those protesters believed to have committed criminal offences.
Garda sources said a number of protesters assaulted members on duty, with a small number repeatedly targeting several gardaí. Others would be investigated for public disorder and criminal damage.
Footage shot by both gardaí and protesters would be used to ground any prosecutions.
Garda sources said protester footage had proven “particularly useful” in the past, with some clips of Wednesday’s events having already been published and studied by gardaí.
Former minister for justice Alan Shatter was blocked trying to enter Leinster House car park in his car, later taking to Twitter to describe as “anti democratic fascist thuggery” the actions of some of those involved.
Labour Party senators Mark Moran and Derek Landy abandoned their cars after Kildare Street was blocked by a group of several hundred protesters, who later engaged in a sit down protest on the road.
The group began gathering at about 12.30pm, with a small number still present by the time many Oireachtas members were leaving at about 10pm.
Commissioner O’Sullivan was on Wednesday contacted and invited to appear before the CPP to discuss security around Leinster House.
Oireachtas members being blocked going to or from the Dáil or Seanad is regarded as an attack on the parliamentary process.
The committee is chaired by the Ceann Comhairle Seán Barrett and is made up of nine TDs representing the main political parties and independents. It oversees Dáil procedures and at times conducts investigations into events there.
