Mayor Kirk Caldwell’s past use of a property tax exemption for historic homes that allowed him to pay only $100 to $300 for several years has come back to haunt him as the city considers raising property taxes to cover rail deficits.

In a recent letter to the Honolulu Star-Advertiser, Caldwell sought to correct “the inaccurate perception from several of your letter writers that I pay only $300 in real property tax.”

He said he owns a historic home, but “even before I became mayor, my wife and I voluntarily decided not to take the deduction even though we still participate in the program.”

It’s true that Caldwell and his wife, bank executive Donna Tanoue, no longer claim the deduction for their Manoa home, but to say they chose not to take it “even before I became mayor” is somewhat misleading without further explanation.

The couple claimed the tax exemption in 2007, when Caldwell was House majority leader, and was still taking it from 2008 to 2010, when he was city managing director and became acting mayor after Mufi Hannemann resigned to run for governor.

The exemption is intended to help owners of state-certified historic homes defray the costs of maintaining their properties.

Caldwell’s participation, along with about 250 others, was revealed in a 2010 Star-Advertiser story by Rob Perez reporting that the program, generous by national standards, cost the city nearly $1 million in lost taxes and suffered from lax enforcement of rules requiring that the homes be publicly viewable.

Caldwell lost his bid to retain the office that year to Peter Carlisle, and the couple continued to claim the tax exemption in 2011.

When Caldwell again ran for mayor in 2012 — after the city tightened rules for the deduction — they opted out, as did several other owners of historic homes.

According to city records, Caldwell and Tanoue paid $100 annually in property taxes from 2007 to 2009 and $300 in 2010 and 2011, when the tax was raised.

In 2006, they paid $6,818 in taxes on their property, which the city valued at the time at $1.88 million. All but $100 of that $6,818 was credited back after they were approved that year for an historic homes exemption.

After opting out of the program in 2012, taking only the $80,000 owner-occupant exemption, they paid $6,088 in taxes on an assessed property value of $1.81 million.

By 2016, the value had increased to $2.34 million and they paid $7,918 in taxes. For 2017, their property is assessed at $2.68 million.

With the Legislature deadlocked on extending the rail excise tax surcharge, Caldwell and the City Council are moving to remove the ban on using property taxes to pay for rail.

“I pay property tax like other taxpayers, and I don’t want to see my property tax increase either,” he said in his letter to the Star-Advertiser.

Reach David Shapiro at volcanicash@gmail.com.