Rep. Jim Matheson (D-Utah) on Tuesday became one of the first Democrats to publicly declare he will vote to hold Attorney General Eric Holder in contempt of Congress, breaking from his party on what is expected to be a mostly party-line vote Thursday.

“Utahns expect and deserve transparency and accountability from government officials, especially when a tragedy such as the death of a U.S. Border Patrol agent occurs. It just compounds the tragedy when both sides play politics instead of releasing the facts,” he said in a statement, adding: “Sadly, it seems that it will take holding the Attorney General in contempt to communicate that evasiveness is unacceptable. It is a vote I will support.”

It’s not clear yet how many Democrats will defect from their party and support the contempt resolution, which comes as the White House and Republicans in Congress have engaged in an increasingly tense clash over the Fast and Furious “gun walking” scandal.