Minnesotans willing to wade through campaign-finance data deserve to be commended. Their due diligence for democracy outs influence-seeking donors and pushes politicians to keep constituents' best interests at heart, not those of special interests.

The citizens willing to do this unglamorous legwork in the interest of government accountability also deserve data that's accurate and complete, particularly if the information is published by a state or federal agency. For all the good questions citizens have about big money's political purchasing power, they shouldn't have to wonder about the data's quality.

Embarrassingly, that's not the case in Minnesota, a state long known for its good governance. In a Nov. 9 story highlighting the value of the news media's watchdog role, Star Tribune reporters Glenn Howatt and Rachel E. Stassen-Berger found a shocking number of errors in the online, searchable files of the Minnesota Campaign Finance and Public Disclosure Board.

Advocates for government accountability, especially those without easy access to the apparently more accurate paper records at the agency's St. Paul offices, rely heavily on the website to analyze fundraising by state political candidates and campaigns. But faith in the agency's online data clearly has been misplaced.

The reporters focused on "transactions among campaigns and groups," such as those from political action committees to campaigns. In reviewing more than 100,000 records, they found "thousands of instances in which political groups reported receipt of a contribution that no group reported giving. Similarly, some groups reported giving donations that no group reported receiving.''

About one in seven of the records examined contained errors or inaccuracies, with problems found in both Democratic and Republican information. The sums of money caught up in the discrepancies were substantial. About $20 million over the past 10 years appears to have not been recorded accurately in the agency's online files — between 14 percent and 16 percent of the total donations the reporters looked at for the past decade.

"A slap at Minnesotans,'' is how Meredith McGehee, policy director of the Campaign Legal Center in Washington, D.C., termed the errors uncovered by the newspaper. McGehee also questioned how the agency failed internal quality control processes designed to catch and fix mistakes in this public database.

Edwin Bender, an expert with the Montana-based National Institute on Money in State Politics, said the errors are disappointing but not surprising. Across the country, agencies like Minnesota's are small and often a target for cost-cutting, given that both political parties would rather avoid a bright spotlight on how money flows in campaigns. "Almost to a letter, they're underfunded. And they're being whacked across the country, especially if they do their job,'' Bender said.

The agencies are also typically trying to do too much with too few people, he said. Their first job is ensuring that the candidates have filed information and complied with general reporting laws. They also investigate complaints. The "pretty massive job of auditing" is down further on the priority list, Bender added.

To his credit, the Minnesota agency's executive director, Gary Goldsmith, is taking action to improve the online data, though it's still troubling that the agency didn't root out the problems on its own. In an interview, Goldsmith echoed Bender's concerns about limited resources.

According to a December 2012 memo, the agency's $689,000 budget was the lowest since 2003. The memo also said lawmakers in recent budgets have provided less funding than recommended by the governor.

At the same time, Goldsmith's comments suggested that the agency is only belatedly understanding the database's critical role in the agency's mission. That needs to change.

Rep. Steve Simon, DFL-St. Louis Park, has issued a welcome call to hold a legislative hearing to review and improve the database. Lawmakers need to follow through. Money is flowing in massive sums through the political system in the wake of the controversial U.S. Supreme Court's Citizens United decision. Databases like Minnesota's — when accurate and complete — are a critical check on big-money special interests.