The Justice Minister Frances Fitzgerald says the water charge protest which left the Tánaiste trapped in her car for two hours was "unacceptable" and "frightening".
Joan Burton was hit by a water balloon while eggs were pelted at her car as protestors banged on the vehicle.
Anti Austerity Alliance TD Paul Murphy, who took part in the Jobstown demonstration, says the Tánaiste was "hamming it up" and looking to play the victim.
Frances Fitzgerald said Ms Burton behaved admirably, and the protesters crossed a line.
She said: "I thought she behaved with great dignity - it's a very difficult situation. I've been in that situation myself for a shorter period - it is very frightening and intimidating.
"There is absolutely a place for protest, for peaceful protest".
"We understand the concerns that people have had about water charges, but it is not acceptable to behave as some people behaved at that protest."