Senators allied to the Azimio la Umoja Coalition have spoken after the staged a walkout on Investment, Trade and Industry CS Moses Kuria.
The CS was among three Cabinet Secretaries who appeared before the senate plenary on Wednesday.
According to the Azimio senators, the CS has been violating the Constitution with his recent attacks on the media, and they would not seat and watch the Senate give him a chance to clear his name.
The Senators said they took an oath to defend the Constitution and would not be a party to what was going on in the Senate.
"Moses Kuria is the poster child of hate speech and ethnic contempt in this country. He has a very acerbic tongue. He is a staff of legend in this country," Sifuna said.
The opposition members said they raised an objection with Speaker Amason Kingi who ruled against them, and they were not going to be party to the proceedings.
They said it was baffling that Kuria would be allowed to address an honourable house like the Senate.
"For somebody who has used such vile language we cannot even repeat here, directed at members of the press to be allowed to speak to members of the Senate and to even receive coverage from some of your media houses is baffling," Sifuna said.
Senate Minority leader Stewart Madzayo said leaders should not allow Parliament to be owned by characters like Moses Kuria.
He insisted that he should not even be allowed to hold the position in the Cabinet.
"It's important such kind of persons should not be allowed to hold positions of cabinet secretary. They don't deserve it and should be given a total blackout by the media," he said.
