Sen. Rand Paul (R-Ky.) said Monday that will vote against confirming President Donald Trump’s nominee for attorney general, William Barr, citing his record on privacy issues.

“I’m a no,” Paul said in brief interview. “He’s been the chief advocate for warrantless surveillance of U.S. citizens. I think that the Fourth Amendment should protect your phone calls and your bank information. People shouldn’t be allowed to look at it without a warrant.”

Paul previously criticized Barr’s record on surveillance issues, including his support of the Patriot Act.

The Senate is expected this week to vote on Barr’s final confirmation. Despite Paul’s opposition, Barr is expected to be confirmed with near unanimous support from Republicans. Moderate Republicans like Sens. Mitt Romney (R-Utah) and Cory Gardner (R-Colo.) have said they will support Barr’s nomination. In addition, Democratic Senator Doug Jones of Alabama said last week he would vote to confirm Barr.