Hawai'i politicians who have donated more money to community groups than state law allows are facing scrutiny — and hefty fines — after a lengthy investigation of campaign records.

The state Campaign Spending Commission agreed Wed-nesday to seek a $950 fine from Sen. Brian Taniguchi, D-10th (Manoa, McCully), for exceeding the $4,000 donation limit for a Senate race.

Taniguchi campaign treasurer Isaac Choy said the violation had been inadvertent, and commission director Barbara Wong said there is no evidence to suggest otherwise.

Other politicians appear to have similar problems that involve more substantial amounts. One case headed for a ruling involves $17,000 in excess donations, Wong said.

Taniguchi's fine is believed to be the first since a 2000 law set new limits on the age-old practice of shelling out campaign cash to youth sports teams, nonprofit organizations and other community groups.

Politicians who make such donations generally say they want to help worthy causes and legitimate groups that benefit their communities.

But the donations have sometimes been criticized as blatant efforts to buy popularity and support in the districts that candidates are seeking to represent.

Investigators have reviewed a three-year backlog of campaign records for excess donations or other campaign violations, Wong said.

Taniguchi's trouble stemmed from a $3,000 donation his campaign committee made to Roosevelt High School, which was raising money for a new athletic track and other improvements.

Since his campaign had already made nearly $4,000 in other community donations within the same four-year election period, the money given to Roosevelt put Taniguchi $2,945 over the limit.

Investigators spotted the problem after the campaign listed the donations in reports filed with the commission, Wong said.

"It was clear that they weren't trying to hide anything," she said.

Choy, the campaign treasurer, said he had mistakenly believed a computer program that tracks spending had been set up to warn of excess donations.

"Had we known we gave too much, we could have corrected the error," he said.

Taniguchi is a Roosevelt graduate and wanted to help the 75-year-old school, said Choy, also a school alumnus. Taniguchi and his campaign committee have not decided whether to pay the fine or dispute it, Choy said.

Taniguchi won re-election unopposed last year, and was named chairman of the Senate Judiciary and Labor Committee last month.

He did not attend Wednesday's hearing because he is on the Mainland for a family vacation, Choy said.

Donation limits per election period vary by office sought, from $2,000 for state House and certain county races to $6,000 for governor.

Reach Johnny Brannon at jbrannon@honoluluadvertiser.com.