The Senate Judiciary Committee on Thursday passed an amended version of legislation aimed at shielding special counsel Robert Mueller—and all future special-counsel appointments—from political interference. The bill was approved 14 to 7, with four Republicans voting in favor. Sens. Thom Tillis (R-N.C.) and Lindsey Graham (R-S.C.), the GOP co-sponsors of the effort, along with the committee’s chairman Sen. Chuck Grassley (R-IA) and Sen. Jeff Flake (R-AZ), joined all Democrats in supporting the legislation. The effort was likely only symbolic, though, as Senate Majority Leader Mitch McConnell (R-KY) has said he would not bring the bill to the Senate floor for a vote. Ahead of Thursday’s committee vote, Republican senators argued that the legislation, as written, was unconstitutional but said Mueller’s investigation should continue unimpeded. Sen. Orrin Hatch (R-UT) warned President Donald Trump that he could face impeachment if he fires Mueller. The legislative effort was launched last summer as lawmakers grew increasingly concerned that the president would move to fire Mueller, who is investigating Russian-election meddling and possible collusion between Trump associates and Russian operatives.