The Democratic Alliance leader Mmusi Maimane says the party will go to court over the conduct of parliament protection officers, Independent Online (IOL) reported.
This comes after the Economic Freedom Fighters (EFF) came to blows with the protection officers during the State of the Nation Address (Sona) in Parliament on Thursday night.
On Friday, Maimane hosted a press briefing, saying the DA wants President Jacob Zuma's deployment of unceremonial soldiers at Sona to be declared unconstitutional.
Maimane raised a point of order in the House on Thursday objecting to the use of teargas in the public gallery, and said it had become "unsafe" to remain in the house.
"I think without doubt, this Parliament has become colonised by the executive. Jacob Zuma is now using stun grenades, teargas, [and] the military to defend the person who has violated the Constitution. And now, the speakers of Parliament have also been co-opted in destroying the Constitution of the Republic."
Maimane said on Thursday outside Parliament: "There was teargas in the gallery where all our guests were. Teargas was deployed in the gallery of Parliament. This is a serious matter which violates the very essence of our Constitution. It can't be."