The Senate Homeland Security and Governmental Affairs Committee voted to authorize a subpoena related to the GOP investigation into Hunter Biden and Burisma Holdings on Wednesday.

Senate Homeland Security Committee Chairman Ron Johnson opened a vote to subpoena Blue Star Strategies, which is accused of trying to influence State Department policies. The consulting firm worked with Ukrainian natural gas company Burisma Holdings while Hunter Biden was still on the board.

The vote, originally intended to take place last week, was postponed for one week “out of an abundance of caution, and to allow time for [committee members] to receive additional briefings.” Despite initial resistance to the idea, Utah Senator Mitt Romney joined fellow committee members in a unanimous vote in favor of the subpoena.

Blue Star Strategies CEO Karen Tramontano sent a letter to Johnson ahead of the vote, asserting their history of cooperation and questioning the need for a subpoena after the firm has already volunteered for an interview. Tramontano also reminded Johnson that the firm has already provided documents related to “meetings with the U.S. government regarding Burisma.”

“At every opportunity we have indicated to the committee that it is our intention to cooperate. At no time have we ever stated or indicated in any way that we would not cooperate,” Tramontano wrote. “Therefore, we are puzzled, despite our willingness to cooperate, why the committee is proceeding to vote on a subpoena.”

Democrats have pushed back against the investigation, suggesting that its motives are purely political. Johnson, however, disagrees. “This subpoena furthers the committee’s work to address the many unanswered questions about this effort and potential conflicts of interest,” Johnson spokesman Austin Altenburg said. “It is unclear why anyone would want to help Blue Star Strategies continue to hide what happened here.”

On Tuesday, California Senator Kamala Harris called out Republican lawmakers for neglecting pandemic business in favor of pursuing the investigation:

Rather than prioritize providing important oversight that will protect Americans from the unprecedented threat posed by this pandemic, you have continued to pursue partisan political matters – such as the markup scheduled for this Wednesday on the issuance of a subpoena – that do nothing to help the millions of constituents that we serve. This is a clear abdication of responsibility.

Hunter Biden and his father, former vice president and de facto Democrat presidential nominee Joe Biden, stand accused of shady dealings with Burisma Holdings and deliberate manipulation of foreign policy for profit. As previously reported:

In 2014, Burisma appointed Hunter Biden, the youngest son of former Vice President Joe Biden, to its board of directors. The board appointment coincided with the elder Biden serving as the Obama administration’s point person for Ukraine, and as Burisma’s chief executive officer stood accused of money laundering. Hunter was paid $83,000 per month to serve on the board, despite his lack of expertise in the oil and gas industry.

President Donald Trump has vowed not to let the issue go. “That will be a major issue in the campaign. I will bring that up all the time because I don’t see any way out. I don’t see any way for them — I don’t see how they can answer those questions. And maybe they can. I hope they can,” the president told host Sean Hannity. “I’d actually prefer it that they can. But I don’t believe they’ll be able to answer those questions. That was purely corrupt.”