Republican leadership in Washington has a serious mutiny problem. Amid roiling concerns about a disconnect between House and Senate GOP leadership—and underscored by the still wary relationship between the republican establishment and the tea-party—Senator Ted Cruz (R-TX) defied the republican orthodoxy by questioning the integrity of Senate Majority Leader Mitch McConnell (R-KY). The Texas Senator and Presidential candidate first accused McConnell of lying and later attempted to change Senate procedures in order to push for an Iran-related amendment. In response to Cruz’s actions, the Republican leadership fired a broadside. Numerous Republican Senators expressed their anger at Sen. Cruz for violating Rule 19 of the Senate, which makes very clear that no senator is to impugn the integrity of another senator. When Sen. Cruz came to the floor looking for a second on a roll call vote, McConnell and his allies refused to grant it. But the tiff soon turned into an all-out brawl when the Majority Leader uncovered an email from Sen. Mike Lee’s (R-UT) office to conservative activists discussing a plot to use an Obamacare vote as a political weapon against Senate leadership. This prompted McConnell to call the GOP into a closed door session, where he and other Republican leaders asserted their dominance by making every GOP senator read the email and calling for unity in the GOP. Whether or not Cruz’s contest with Senate leadership is related to his presidential campaign, the broader fallout shows that the power struggle between establishment and tea party Republicans is getting heated.