Updated

Demanding explanations for a $1 billion cost overrun, a House panel Wednesday issued a subpoena to the Department of Veterans Affairs for documents on how the cost of a Denver-area VA hospital ballooned to almost $1.7 billion.

That figure was nearly triple earlier estimates.

The subpoena by the House Veterans Affairs Committee also seeks documents related to millions of dollars spent on artwork and ornamental furnishings at VA offices nationwide, including more than $6.4 million spent on the Palo Alto, California, health care system.

The chairman of the veterans panel, Rep. Jeff Miller, R-Fla., said it was "unfortunate that VA's continued lack of transparency has led us to this decision" to issue the subpoena, but contended that lawmakers had little choice.

"We will not accept VA trying to pull the wool over the eyes of this committee and the American people for poor decision-making and waste of funds," Miller said.

The subpoena was served Wednesday and gives the VA until Sept. 28 to respond.

The subpoena is at least the fourth the House panel has issued since 2014 amid continuing frustration over the VA's performance following the wait-time scandal that led to the ouster of the VA secretary and a $16 billion overhaul approved by Congress.

Veterans on secret waiting lists faced scheduling delays of up to a year, and as many as 40 veterans died while awaiting care at the Phoenix hospital, according to an investigation by the VA's inspector general.

Miller and other Republicans say the VA has been slow to fix problems and should have fired some employees for wrongdoing.

The GOP-led panel approved Wednesday's subpoena by voice vote. Democrats objected, saying they worried that documents related to the Aurora, Colorado, hospital could jeopardize agency whistleblowers who have helped officials learn the true scope of the cost overruns at the facility, considered one of the biggest boondoggles in the agency's history.

Miller and other Republicans said the committee has a track record of protecting whistleblowers and the subpoena will not lead to the release of personally identifiable information.

The committee has been seeking documents related to the Denver hospital for months. The VA gave Congress a summary of an internal inquiry, but not the supporting documents, despite repeated requests from lawmakers.

The summary hasn't been made public, and the VA has not complied with an open records request from The Associated Press to release it. Deputy VA Secretary Sloan Gibson has said making the documents public could have a chilling effect on future internal investigations.

The summary, in conjunction with the other information provided to lawmakers should "provide sufficient information to inform the committee about how the (investigation) was conducted, the reasons for its conclusions and rationale for corrective actions that the department has taken to ensure that there is no repeat of the missteps made on this project," Gibson said in an Aug. 19 letter to Rep. Mike Coffman, R-Colo.

Coffman, whose suburban Denver district includes Aurora, is in a tough re-election race. "Veterans and the American people deserve answers on what drove over $1 billion in cost overruns and years of delay" in completing the hospital, he said.

Panel chairman Miller said he has been seeking documents related to art contracts for more than year, following reports that the VA's Palo Alto Health Care System spent more than $6.4 million on artwork and other furnishings, including two sculptures that cost nearly $500,000.

The subpoena seeks information on purchases of artwork and ornamental furnishings nationwide since 2010.

VA spokeswoman Walinda West said in a statement that while department officials "must be stewards of taxpayer dollars, we also know that providing comprehensive health care for patients goes beyond just offering the most advanced medical treatments. Artwork is one of the many facets that create a healing environment for our nation's veterans."