A lawyer acting for alleged victims at the centre of an inquiry into alleged historical child sex abuse at Westminster said appointmenting Baroness Butler-Sloss was "almost like appointing a close relative of the head South Yorkshire police ... to be in charge of the Hillsborough inquiry."
Alison Millar told ITV News "it's just not really very appropriate."
Her comments came after it emerged that Baroness Butler-Sloss' brother Sir Michael Havers was attorney general at the time when many of the allegations were made and had tried to prevent ex-MP Geoffrey Dickens airing claims about a diplomat in Parliament in the 1980s.
ITV News Political Correspondent Libby Wiener reports.
The Baroness says she did not consider the "difficulties" caused by her background and family connections to the child sex abuse inquiry.
Questions have been raised of former High Court judge Baroness Butler-Sloss since her appointment last week.
22 police officers are now assigned to Operation Fernbridge - the probe into claims of a Westminster cover-up of sex child abuse.