COEUR d'ALENE - Attorneys argued before the Idaho Supreme Court on Monday over whether an Athol legislator's appeal to the Idaho Board of Tax Appeals is valid, with much hinged on protections allowed for lawmakers.

The state's highest court is tasked with deeming if Rep. Phil Hart correctly filed his appeal of the Idaho State Tax Commission's denial to grant him several years of business deductions, associated with the lawmaker's years of boycotting income tax.

At the heart of Monday's debate was whether Hart had filed his appeal in time. Statute required Hart to appeal within 91 days of the October 2, 2009, receipt of notice of the tax commission's decision. Although some consider the filing deadline fell on Jan. 4, taking the New Year's holiday into account, Hart had filed the appeal on March 30, 2010.

Hart's attorney, Starr Kelso, contended that because the 91-day window fell into the protective time frame of the legislative session, Hart was not obligated to file until after the session wrapped up at the end of March.

Kelso alluded to the Idaho Constitution, chapter 3, section 7, stating that legislators shall not be liable to any civil process during the legislative session or 10 days before.

"The legislators are not there to deal with personal issues," Kelso said of the legislative session. "They're there to act on behalf of the people's interests."

But William von Tagen, deputy attorney general with the State Tax Commission, argued that such protection doesn't apply in this case.

That measure only relates to civil processes, von Tagen said, and he argued that an appeal is an administrative process. He also noted that filing an appeal was not a process being imposed on Hart by the courts, but a voluntary action he had the option of participating in.

"He's not being subject to the process, he's availing himself of it," von Tagen said.

Von Tagen noted that Hart sent a letter to a deputy attorney general in December 2010, explaining his intent to file after the session.

"It was an act deliberated upon," von Tagen said.

Hart's appeal filed on March 30, von Tagen added, only included a partial payment of the deposit to file an appeal, with a letter promising the rest would come.

"The only relevant fact is his appeal time ran out on Jan. 4," von Tagen said.

Kelso responded that the Idaho Constitution intends civil process to be an umbrella term that includes all civil procedures, appeals included.

"It says, 'any civil process," Kelso said.

Some of the justices questioned the meaning of the constitution's phrase that legislators shall not be "liable" to processes during the session.

"Doesn't that imply compulsion, requiring someone to do something?" asked Justice Daniel Eismann.

Justice Warren Jones noted that an appeal might not fit into that.

"He doesn't have to appeal. There is no compulsion," Jones said. "He's not being subject to a process, it's if he chooses to use that process."

The justices will now take as much time as needed to issue a decision, which could stretch into weeks or months.

Hart said after the court arguments that he hopes the justices will rule in favor of what he considers the plain language of the constitution.

"They're arguing over whether or not this was an administrative process or civil process," he said. "But back in '89, when the state of Idaho's constitution was ratified, they probably didn't think in terms of administrative processes. They probably thought either civil or criminal."

He noted that the tax deductions he is seeking span the late 1990s to early 2000s, the same time frame that he refused to pay income tax because he considers it outside the government's authority.

Although Hart didn't know the exact amount, the deductions total several hundred thousand dollars, he said. They include expenses for his engineering office like payments for employees, office rent and other business costs "everyone else is entitled to take," in deductions, Hart said.

He added that the temporary postponement of a civil process for a member of the Legislature isn't for the lawmaker's benefit.

"It's for the benefit of the people he is representing, so he can give his full attention to his work while the Legislature is in session," Hart said. "In my work as a legislator, I've tried to handle as many issues as I can pile on."