Homeless advocates have filed the first legal challenge to the city's sidewalk nuisance law which went into effect in July.
Brian Brazier, an attorney for De Occupy Honolulu which has set up camp at Thomas Square, said the confiscation of personal belongings constitutes an unreasonable seizure.
The federal court lawsuit comes as the city is preparing to clear out the homeless camp at Pawaa's In-Ha Park. The city says it will conduct maintenance at the park through Oct. 9.
"The city comes like thieves in the night. If someone broke into your home and took all of your worldly possessions, you'd have a problem with that," Brazier said.
"We seek to have as many provisions struck down on their face value as unconstitutional and have the city's enforcement deemed unconstitutional."
The law, introduced as Bill 7, allows city workers to remove the tents and other personal belonging of homeless residents at city parks. The owners have 30 days to get back their property if they pay a $200 fine.
The city says its enforcement actions stand on firm legal ground.
"I feel very confident that in terms of the measures we have signed into law that they are valid," said Mayor Kirk Caldwell.
The mayor says the new law is making a dent in the homeless problem at city parks.
"We've checked with different providers who shelter the homeless. We've been told there's been an up tick in people coming into the shelters," he said.
At the beginning of the enforcement actions, the city said it was collecting about 11 tons of material a week. That's down to about 3 tons a week.
Some say the city's enforcement actions only work for so long.
"Very often within a half an hour of their sweep, the homeless come back, so they don't last that long," said Gregory Smith, product advisor and sales at Saunders Piano, which is located next to In-Ha Park.
"We have customers who won't come back because of the homeless."