Updated: July 14, 8:03 p.m.

Republicans on the Senate Finance Committee are asking Chairman Max Baucus (D-Mont.) to hold a hearing to consider President Barack Obama’s recess appointment of Donald Berwick to serve as administrator of the Centers for Medicare and Medicaid Services.

In a letter sent to Baucus on Wednesday, Finance Republicans requested that the chairman ask Berwick to appear before the committee to answer questions. The CMS falls under the purview of Finance, but a hearing on Berwick’s nomination was never held. Obama instead chose to install him through a recess appointment over the July Fourth break.

“This recess appointment will have imposed an injustice on Dr. Berwick himself if it results in preventing him from being able to answer the legitimate questions raised about his nomination,” wrote the 10 Finance Republicans, including ranking member Chuck Grassley (Iowa). “If he is not provided opportunity to provide his qualifications in the usual process, it casts a shadow over his legitimacy and authority to serve as Administrator during a critical time for CMS.”

Baucus has joined Republicans in expressing his disappointment in Obama’s decision to circumvent the usual Senate confirmation process, but the Finance chairman said Tuesday that he had no plans to ask Berwick to appear before the committee in a manner that would substitute for a confirmation hearing.

However, Berwick will eventually have to appear before the Finance Committee, given that the panel has oversight of the agency.

“Chairman Baucus has expressed disappointment that rather than going through the standard nomination process, Dr. Berwick was recess appointed,” a Finance Committee aide said Wednesday night. “Ensuring that health care reform is implemented properly to deliver the high-quality care and affordable coverage the law was designed to produce is an oversight role Chairman Baucus takes seriously, and he fully expects that CMS Administrator Berwick will testify before the committee on that topic and other important health policy matters in the near future.”

Senate Republicans have been fuming over Obama’s decision to install Berwick using a recess appointment, and they talked openly Tuesday of retaliating in some fashion. They would most likely choose to block the confirmation of other White House nominees.

Senate Democrats said the recess appointment was regrettable but understandable, given that they believe the GOP would have subjected Berwick to unreasonable scrutiny during a confirmation hearing.

Berwick has expressed support for a single-payer, government-run health care system in the past, leading many Republicans to question how he would operate as CMS administrator.