John Eastman, a conservative lawyer who backed former President Donald Trump’s efforts to question the 2020 election results, is suing to block subpoenas issued by the Jan. 6 select committee for his cellphone data.

Eastman filed the complaint in the D.C. federal court on Tuesday, making it at least the third federal lawsuit seeking to quash such subpoenas. The complaint is signed by Charles Burnham, an attorney with the firm Burnham & Gorokhov.