Vera Baird says judge should withdraw as her panel would have to examine if her brother played down abuse claims

A former solicitor general has called on Lady Butler-Sloss to stand down as chair of the inquiry into child abuse over a family conflict of interest.

Vera Baird, the police and crime commissioner for Northumbria who served as Labour's solicitor general from 2007 to 2010, said the home secretary, Theresa May, had made an error in appointing Butler-Sloss because her brother had served as attorney general in the 1980s.

Butler-Sloss, a former president of the family division of the high court, has faced intense pressure since her appointment last week because her brother, the late Sir Michael Havers, served as Margaret Thatcher's attorney general from 1979 to 1987. The Butler-Sloss panel would have to examine whether Havers played down allegations of child abuse during that period.

Baird told the Today programme on BBC Radio 4 on Monday: "If she were in a court case presiding over it and her brother were mentioned as someone she may have to investigate, she would of course withdraw due to a conflict of interest. The conflict of interest is even bigger here where we have a vulnerable community of people who say that they have been not allowed to get justice.

"It is her task to look into it. It has got to be done by somebody who is an outsider to this, who is completely independent. Without wanting to descend totally to cliche, justice must not only be done but it has to be seen to be done."

Campaigners on child abuse last week called on Butler-Sloss, 80, to stand down after she was appointed by the home secretary to chair a panel of inquiry that would examine the extent to which public bodies failed to investigate allegations of child abuse. Alison Millar, a lawyer who is representing some of the victims of child abuse, likened the appointment of Butler-Sloss to asking a relative of the head of South Yorkshire police to chair the Hillsborough inquiry.

The retired judge faced renewed pressure over the weekend when the Times reported that she kept allegations about a bishop out of a review of how the Church of England dealt with two priests allegedly involved in paedophilia. Butler-Sloss reportedly told a victim that she did not want to name the bishop because "the press would love a bishop". Bishop Peter Ball, the former bishop of Lewes and of Gloucester, was charged this year with indecent assault and misconduct in a public office.

Baird said Butler-Sloss's personal qualities were "immaculate", but she added: "Michael Havers [her brother] was attorney general from 1979 to 1987 and he then became lord chancellor. It would have been up to him, had there been reports coming through, as the chief law officer, to make sure they were investigated. I have no reason to know whether Michael Havers was ever given any information or whether he acted upon it or didn't. But she is going to have to investigate the role played by her late brother."

The former solicitor general added: "The current issue surely is should somebody be investigating something in which their brother has been named, however he may in due course be exculpated? Is this going to satisfy this very vulnerable company of people who feel that the establishment has kept them out of justice already?

"I think it is an error. I don't know if she, when agreeing to take it on, knew the implications for herself and for her family. She is a very dutiful person, she would feel she should take it on if she was asked to do so. The error is the home secretary's. It needs correcting."

Sir Mathew Thorpe, who served alongside Butler-Sloss in the court of appeal, acknowledged the concerns raised by Baird. But he said Butler-Sloss's record as a judge and as chair of the Cleveland child abuse inquiry put her in a strong position to chair the new panel.

Thorpe told the Today programme: "Of course it [the conflict of interest] is a relevant consideration. But it has to be weighed against other relevant considerations, including her unrivalled qualities.

"She has a high sense of duty to serve wherever her contribution may be of value. This is well illustrated by all the work she has done in the House of Lords, where she has been very active on all family justice issues."