Education Secretary John Swinney has been asked to detail meetings between government officials and witnesses to a Holyrood committee regarding named person legislation.
The written request comes after Mr Swinney was asked to provide assurances in November over questions on whether "the Scottish Government sought to directly influence evidence to the committee".
The Scottish Parliament's Education and Skills Committee has written to the Cabinet Secretary as some members are concerned his previous answers "did not fully address matters raised".
Now, the committee has set out 16 points for Mr Swinney to address with a "detailed timeline" including dates that witnesses providing evidence were approached by Scottish Government officials, ministers or special advisers and the "rationale" behind the contact.
Further details requested are whether Scottish Government officials acted unilaterally regarding meetings with witnesses or if Mr Swinney or his advisers gave them instruction.
The letter from committee convener James Dornan states: "To give parliament its place, any assurances offered to witnesses by the government on ways in which policies will be changed or supplemented should be raised with the relevant committee first.
"This must be the case as this committee moves forward with scrutiny of the Bill, anything less than this could be considered a slight on this committee."
It adds: "The committee understands that, in general, engagement with stakeholders is important to the government in developing legislation that is as robust and as applicable to those required to implement it as possible."
Labour's education spokesman Iain Gray praised the committee's actions, saying it is "demanding answers on the suspicion that Scottish government exerted pressure on their witnesses prior to evidence on Named Person Bill".
The row surrounds evidence given proposed legislation brought forward in response to a legal challenge to the named person policy.
The named person scheme would involve a single point of contact, such as a teacher or health visitor, being appointed to look out for the welfare of every child.
The Children and Young People (Information Sharing) (Scotland) Bill aims to address the Supreme Court's finding last year that information-sharing provisions in the original legislation were incompatible with human-rights law and requires ministers to publish a code of practice for professionals on how information should be shared.
Last year, MSPs agreed to remove a key parliamentary deadline for the new Bill, paving the way for delay to the named person scheme.
The committee refused to publish a report on general principles of the Bill, required to enable the legislation to proceed to the next parliamentary stage, until ministers provide a draft code of practice instead of an illustrative version of it.