Senator Chris Murphy has dismissed claims by the supreme court justice, Samuel Alito, that the Senate has “no authority” to create a code of conduct for the court as “stunningly wrong”.

The Connecticut Democrat made those remarks in an interview on CNN’s State of the Union on Sunday, adding that Alito “should know that more than anyone else because his seat on the supreme court exists only because of an act passed by Congress”.

“It is Congress that establishes the number of justices on the supreme court,” Murphy said. “It is Congress that has passed in the past requirements for justices to disclose certain information, and so it is just wrong on the facts to say that Congress doesn’t have anything to do with the rules guiding the supreme court.”