Since he first entered politics as a candidate five years ago, Illinois Gov. Bruce Rauner has pledged his commitment to open government.

As he put it during a debate last week with challenger J.B. Pritzker before the Chicago Sun-Times editorial board: “Transparency is great.”

As he fights for re-election, making the declaration is a great move on Rauner’s part — and an easy one. Voters are demanding more and more information about what their governments are doing with their tax money, and every candidate at every level is wise to speak in favor of sharing it with them.

But what Rauner means when he vows to be transparent isn’t so clear, given his administration’s habit of fighting against the release of information. The governor’s office won’t even disclose how often it blocks the release of records sought by the public.

From January 2017 through this June, the governor’s office received more than 500 requests for records under the state Freedom of Information Act, according to a log released to me in response to a FOIA request. The log shows the office received requests from journalists, unions, businesses and independent citizens who wanted copies of the everything from Rauner’s schedule to emails from first lady Diana Rauner.

Yet the governor’s office wouldn’t provide me records showing whether it granted or denied the requests, arguing it wasn’t obligated to under the law.

“Please also be advised that the Governor’s Office is not required to answer questions or generate new records in response to a FOIA request,” one of the governor’s attorneys wrote in a letter.

In other words, Rauner’s lawyer was arguing that his office didn’t have to reveal how it responded to FOIA requests because it doesn’t have those records on hand. That means the governor’s office kept a detailed log of every FOIA request it received, who made it, what it was for and when a response was due — but claimed it didn’t track whether the office ever provided the information or complied with the law.

Either the office isn’t being transparent or it’s not keeping good records.

Even so, the response to my request was more forthcoming than what another Chicagoan, Sarah Jackson, got last year when she asked the governor’s office for a FOIA log: nothing at all. The office never responded to her, according to a summary of the case by the office of Attorney General Lisa Madigan’s public access counselor, which handles FOIA disputes.

When Rauner’s office didn’t acknowledge her request within two weeks, Jackson notified the PAC, which tried to find out what had happened. But Rauner’s office didn’t respond to those inquiries either. In December, the PAC issued a binding opinion ordering Rauner’s office to produce the log.

Jackson’s FOIA request was one of more than 40 appealed to the PAC from January 2017 through this June after Rauner’s office denied them, records from the attorney general show. In addition to Jackson’s case, the PAC ruled three other times that the governor’s office had violated FOIA. On at least 16 other occasions, the governor’s office responded or reached an agreement with the requester after the PAC got involved. Most of the other cases were closed for administrative reasons. The PAC determined Rauner’s office had acted properly in just one of the disputes.

As I found in a recent investigation, the PAC’s office is backlogged with FOIA appeals that often take months or even years to resolve. One of the reasons it gets so many cases is that public bodies around the state resist such requests.

Ann Spillane, the attorney general’s chief of staff, said the obfuscation starts with Rauner.

“We have a governor of Illinois who actively tries to undermine the FOIA,” she said.

But Patty Schuh, a spokeswoman for Rauner, said his administration remains committed to transparency and devotes considerable resources to complying with the law.

“Our teams spend hundreds of hours each week reviewing documents to respond to FOIA requests as completely as possible and in a timely manner,” she wrote in an email. “We’ve produced hundreds of thousands of pages of responsive documents. In addition, the volume produced by individual state agencies under the Administration could number in the millions.”

Schuh described an office barraged with FOIA requests, including many that take long hours to process. She said the governor would be willing to work on “improvements” to the law, which was first passed in the 1980s.

“The law doesn’t adequately account for the current reality that some government bodies, including our office, add hundreds of thousands of emails each year to their records, if not millions,” Schuh said.

But Rauner wasn’t very sympathetic to the burden the law placed on his predecessor, Pat Quinn, portraying him four years ago as a product of the secretive Democratic machine. He promised to bring a new level of openness to state government if elected.

After taking office in 2015, though, Rauner’s administration began arguing that it was exempt from many FOIA requests, including for basic records such as his daily meeting schedules. In September of that year, the PAC ruled against the governor, concluding his calendars were indeed public records.

His office then stopped naming the people he met with, instead using only their initials on the calendars.

Rauner also repeatedly fought to keep state officials’ emails secret. Last week, the PAC issued another binding opinion that said the emails are public records and releasing them doesn’t place an undue burden on the office.

Much as Rauner once went after Quinn, Pritzker has spent the last year hammering Rauner for concealing key decisions and scandals within his administration.

During the Sun-Times debate, for example, Pritzker accused Rauner of flouting FOIA by redacting emails that reporters sought while investigating a deadly outbreak of Legionnaires’ disease at the Illinois Veterans’ Home in Quincy.

“They were blacked out because he didn’t want to let people know what was going on, which was an effort to cover their butts, to make sure that they weren’t held accountable,” Pritzker charged.

Rauner denied any wrongdoing. Instead, he attacked Pritzker for not revealing details of his tax plan, and for getting his own tax breaks after removing toilets at his Gold Coast mansion.

The governor had a point: Neither move was a model of transparency.

Jason Rubin, a spokesman for Pritzker, told me the Democrat will “ensure his administration works in good faith to improve public access to information across all executive agencies,” such as making more data and records available, presumably without the need for FOIA requests. In contrast, Rubin said, “Bruce Rauner has routinely shirked ethics and transparency as governor.”

Yet this week the rivals revealed similar notions about openness, and especially its limits. Each released tax records showing more than $50 million in income last year. Each declined to let the public see schedules or attachments showing deductions and other financial details, though news reports have found they each have networks of investments that extend to offshore tax shelters.

Some claims of transparency are easy to see through.