Opposition Leader Mark McGowan has condemned protesters who occupied the street outside Premier Colin Barnett's Claremont home, one of whom scaled a fence into the property.
A 20-year-old man was arrested and charged with trespass after allegedly locking himself to the property's gate.
Mr McGowan said it was "outrageous that people come and protest outside the Premier's house and they should hang their heads in shame".
"I hope that police throw the book at them.
"The Premier and his family should not have to go through anything like this at his house.
"And I think all West Australians of any political persuasion will think this is an outrage."
Officers scaled the fence to apprehend the man.
The 20-year-old man is a member of Forest Rescue, who joined the protest this morning after Aboriginal protesters arrived to 'occupy' the street, saying they would not move until Mr Barnett received a lengthy document outlining a claim for sovereignty.
Protest organiser Marianne Mackay said her group had failed in many earlier attempts to give the document to Mr Barnett and were prepared to stay outside his house “for as long as it takes”.
Forest Rescue hung a banner on Mr Barnett’s front gate at around 8.30am.
Mr Barnett’s wife Lyn was upset at the action and asked protesters to move away from the house or she would call the police.
Police officers arrived around 15 minutes later and began a search of bushes surrounding the home.
They recovered a steel tube in a backpack hidden in verge-side vegetation and called in members of the State protection unit.
Council rangers have asked protesters to move their vehicles from a no-stopping zone outside the Premier’s home and put a dog belonging to one of the protestors on a leash.
A police spokeswoman said the protesters were not breaking the law and she respected their right to protest.
The small group of protesters includes two babies and a well-known activist Sean Gransch.
Ms Mackay said her group had been trying for five months to meet the Premier and was taking the action outside his home because it had run out of other options.
“We are not moving until Colin Barnett comes here and takes this document from us,” Ms Mackay said.
“This is a document that rebuts all their (State Government) claims to sovereignty."
“You have got to be a mining executive or a millionaire to get an audience with the Premier. That’s just not good enough”.
Nyoongar protester Herbert Bropho arrived and told the group that when they needed a rest he would “bring in another mob”.