Speaker of the legislature Linda Reid said in a statement that the gallery was restricted temporarily to allow security officials to review and assess protocols and procedures after protesters were hustled out.
Only guests invited by members of the legislature were granted access to the morning proceedings in the public gallery from where debates and question period can be viewed.
Complete public access to the legislature was restored Tuesday afternoon.
On Monday, a dozen people started chanting, "No consent, no LNG" when the government introduced a liquefied natural gas law up for debate. Security officials removed them from the building.
The protesters said they wanted to draw attention to climate change issues, particularly the government's support of the LNG industry, which would increase harmful greenhouse gas emissions.
New Democrat David Eby called the security measures heavy handed, saying the public should not be denied access to the people's house after some protesters caused a disturbance.
"We're not the hottest ticket in town, I get that," Eby said. "People aren't lining up to come in here, but at the same time when they do show up they shouldn't be told they can't come in because somebody behaved badly the previous day."