The SNP has been accused of undermining Holyrood by giving ministerial insiders key roles in scrutinising their own bosses.
Ministers will face questions in committees from their parliamentary liaison officers (PLOs) – junior MSPs who support more senior SNP colleagues.
Opposition parties branded the move a blow to democratic scrutiny.
Scottish Conservative north-east MSP Alex Johnstone said the SNP had “form in trying to stitch up the Scottish Parliament and block proper scrutiny”.
He added: “The result is that hopelessly flawed laws like named persons have made it on to the statute book.
“We need a parliament with teeth, not one hobbled by SNP cronyism.
“The SNP should do the decent thing and ensure that MSPs employed to assist a minister do not then sit on the committee which is supposed to be holding those same ministers to account.
“Nicola Sturgeon has said she wants a stronger Scottish Parliament – she now needs to act without delay.”
North-east Liberal Democrat MSP Mike Rumbles said putting ministerial insiders on committees fostered complacency.
He added: “A strong democracy needs to have those in power challenged robustly. That can’t happen if people involved in scrutiny are at the same time working for the government.
“The public needs committee members who are relentless in their questioning of ministers, not cheerleaders.
“The SNP have lost their majority and are trying to make sure they get a soft ride from committees.
“We need to understand what impact these appointments will have on the ability of Holyrood committees to do their job. If necessary, the committee appointments must be re-voted by parliament.”
But an SNP spokesman accused the parties of “hysteria” by speaking out against the arrangements they had already agreed to.
He said the responsibilities of PLOs “in no sense” prevented them from scrutinising government.