The Scottish Government must accept all the recommendations made by the elections watchdog so the independence referendum is a "fair and proper" vote, Labour has said.
Patricia Ferguson challenged the SNP administration to "accept in full" the Electoral Commission's recommendations on how the ballot is staged.
She made the plea the day before the commission publishes its assessment of the Government's preferred question for the referendum, which is "Do you agree that Scotland should be an independent country?"
It will also give its assessment of the proposed campaign spending limits.
Deputy First Minister Nicola Sturgeon told MSPs the assessments will carry "considerable weight" with ministers, but the Scottish Parliament has the final say on such matters.
"As with referendums held under UK legislation, it is for the Government to propose the referendum question, the Electoral Commission to test the question and the Parliament to make a final decision," Ms Sturgeon said.
"The Scottish Government will consider the wording of the question and indeed other matters relating to the conduct of the referendum in light of the commission's advice and, of course, the Scottish Parliament will have the final say during its scrutiny of the referendum legislation."
Ms Ferguson, Labour's constitution spokeswoman, said she is disappointed that Ms Sturgeon would not commit to abide by the commission's recommendations. There is a "growing clamour of voices" calling on ministers to do so.
She urged the Deputy First Minister to reassure MSPs that "her belief in independence extends to independent scrutiny too".
"Does she not understand (that) for this referendum to be carried out in a fair and proper manner and, as importantly, to be seen to be carried out in a fair and proper manner, the recommendations of the Electoral Commission must be the guiding principles for the conduct of the referendum, both in terms of the question to be put and the spending limits to be applied?" Ms Ferguson asked.