In the United States, "We the People" are the sovereign. What Q means is that the act of participating in the murder of a U.S. citizen in an effort to overthrow or subvert the U.S. constitutes killing the sovereign or a member of the family of the sovereign. So those who conspired to kill many, such as Seth Rich et al., are guilty of, and will be charged and convicted of, treason, and will be disposed of accordingly. Neat!