The wearing of hoods by gardai policing a housing protest was "not correct", Garda Commissioner Drew Harris has said.
However, he also argued that officers showed restraint "in the face of physical and verbal abuse from a very small minority".
Gardai faced criticism as masked members were assigned to police up to 1,000 people protesting against activists being evicted from a property in Dublin on Tuesday evening.
Garda members stood in front of number 34 North Frederick Street while men in balaclavas from a private security group removed activists from the building.
Mr Harris said that as the atmosphere at the protest grew tense, a small number of public order officers were deployed to ensure public safety.
He said the use of fire retardant hoods by officers for their safety was a matter for the commander on the ground to decide based on a risk assessment.
The form of dress used at the event "was not correct as it is policy that if it is deemed necessary to use the hood then it should be used in tandem with a protective helmet".
Mr Harris said that a deputy commissioner had issued a directive to all garda personnel to reinforce this requirement.
He had also asked for a report on what lessons could be learned from the event.
Mr Harris said gardai respect the right of people to protest peacefully, adding that his organisation's role was to facilitate lawful demonstrations while protecting the rights of others to "do their lawful work safely", in this case the carrying out of an order of the High Court. He said the objective in any such operation was to ensure public safety.
Mr Harris said that members of An Garda Siochana "showed restraint in the face of physical and verbal abuse from a very small minority".
He also condemned alleged racist abuse suffered by a garda member.
"The people who had occupied the building left the building peacefully in accordance with the High Court order," Mr Harris said.
"Subsequent to this, a small crowd failed to leave the area despite repeated warnings from An Garda Siochana under the Public Order Act and five people were arrested."
Of those arrested, two are due to appear before the Criminal Courts of Justice on October 2.
Four people were hospitalised following the incident, according to a statement released by Take Back The City, a network of 18 grassroots activist groups who are "working together to take direct action" against Ireland's housing crisis.
The activists were removed from the property as they had been defying a High Court order and remained in the building for a number of weeks.
Taoiseach Leo Varadkar has defended the right to protest but said it must be non-violent and within the law.
He said in this case there was a High Court order to vacate the premises.
Mr Varadkar also said "like a lot of people, I didn't like to see a private security firm in balaclavas".
The Taoiseach said gardai were wearing hoods and ski masks due to the risk of fire or something being thrown at them, and to protect their identities.
However, he added that in all cases they had their identification badges visible.