The state is cracking down on real estate brokers who don't pay general excise tax on their sales commissions.

Hundreds of residential and commercial real estate agents are suspected of not paying the 4.166-percent tax on commissions they received for brokering property sales over the past seven years, according to the state attorney general and Tax Department.

The attorney general recently filed criminal complaints against about a dozen brokers accused of not paying $390,000 in taxes on $9 million of sales commissions.

In addition, several hundred brokers have been sent civil complaint letters by the Tax Department for less severe cases of suspected GET nonpayments.

"All of Hawai'i's citizens have an obligation to comply with tax laws," Attorney General Mark Bennett said in a statement. "We will continue to vigorously prosecute those who fail to report and pay general excise taxes."

The Tax Department began an investigation after noticing that many real estate agents had not filed general excise taxes for consecutive years during a period that Hawai'i's real estate market raged to record sales and prices.

Stephen Hironaka, the Tax Department's supervisory criminal tax investigator, said the department obtained federal income tax return records of brokers working for Hawai'i's 10 largest real estate firms, and checked to see which brokers reported income but didn't pay general excise taxes.

"These are not one-time occurrences where they don't file taxes for one year," he said. "These are multiple years of nonpayment. They used to file before, then for some reason they stopped."

Hironaka said brokers suspected of failing to file general excise taxes totaling more minimal amounts or in nonconsecutive years were sent letters that ask the recipients to address the matter with tax officials. Those who don't respond will be assessed taxes the department claims it is owed.

The more serious allegations are a criminal matter being pursued by Hironaka.

Failure to timely file a general excise tax return is a misdemeanor punishable by up to one year in prison and a $25,000 fine.

Reach Andrew Gomes at agomes@honoluluadvertiser.com.