RAPID CITY, S. D. – Some public property is less public for critics of government spending.

A group called Citizens for Liberty, which promotes limited government and lower spending, was trying to collect enough signatures outside the Rapid City, South Dakota post office to force a public vote on a proposed $30 million school tax increase.

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Post office employees objected to the activists collecting petition signatures and ordered them to leave.

When they refused, postal employees called the police. After police arrived and the activists still wouldn’t leave public property, 68-year-old Roberta Helmerick was arrested “for failure to vacate after receiving notice,” KOTA reports.

“The persistent refusal of Mrs. Helmerick to cooperate with the post office and police officer throughout the day left us with no other option than enforcement so that we could get back to routine police business,” Chief of Police Karl Jegeris says, defending the arrest of an elderly woman.

“I think it’s actually tragic and it emphasizes the degradation of our First Amendment right,” activist Jordan Mason says.

The post office recently changed its policy to bar such activity on public property.

“We’ve had a history of being able to use petitions here on the property, many, many petitions over many, many years. Something all of the sudden has changed. I don’t know what the problem is but we’re told we can’t ask people to sign this petition on property of the government,” another activist, Norm Christopherson tells the news station.

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The signature gatherers weren’t being hostile and weren’t harassing post office patrons. And they think they had every right to be there.

“We’re trying to just peacefully assemble here at a public post office to get signatures to put the school issue on the ballot and give the citizens the right to vote on a $30 million tax increase over the next five years,” according to Mason.

And the activists say no one complained, that is, of course, except for the government employees.

“It seems like the only people complaining are the postal authorities here, because we have had tremendous, positive remarks from the people who are coming in and out of the post office. In fact for many of them, we don’t have to say anything. We just hold up this little board and they say, ‘Oh, I want to sign that,’” Christopherson says.

The citizens have until the end of the day Friday – today – to gather enough signatures to force a public vote.