TWO Catholic charities are to lodge a legal objection to the choice of chair for the Scottish Government's inquiry into the historic abuse of children in care.

The Congregation of the Poor Sisters of Nazareth and the Daughters of Charity of St Vincent De Paul will seek a judicial review today challenging the appointment of Susan O'Brien QC, who is due to take up the post within days.

Last night a senior civil servant wrote to various parties, including several victims of historic child abuse who have campaigned for more than 14 years to achieve an inquiry, warning them about the action being taken by the charities.

The first hearing will be at the Court of Session in Edinburgh, he said, adding: "Please be reassured that the Scottish Ministers are defending this challenge robustly. It is still intended that Ms O'Brien will take up her position as planned on the 1st of July."

Education Secretary Angela Constance appointed Ms O'Brien last month to head the inquiry which will examine any instance in which a child was abused in care.

She told the Scottish Parliament on May 28 that Ms O'Brien had expertise in human rights and civil litigation. Ms O'Brien also chaired the inquiry into social service failings after the death of 11-month-old baby Caleb Ness in Edinburgh in 2003.

The fear will be that the inquiry will now be derailed in the way that a similar investigation in England was repeatedly delayed when ministers were unable to find a chair acceptable to victim and survivor groups.

David Whelan, a leading campaigner and author of No More Silence, which detailed his own abuse at the hands of convicted paedophile John Porteous while living in a children's home run by Quarriers in Renfrewshire in the early 1970s, said he was disappointed at the action taken by the two charities.

"This clearly demonstrates the imbalance of power here," he said. "If the roles were reversed there is no way the victims and survivors would have the money to mount a judicial review. We would clearly like the appointment of Susan O'Brian to go ahead but we will await the court's decision.

"We have always called for the rights of everybody to be upheld, including those accused of abuse."

Victims and survivors are said to be "fearful" about any prospect of delay, particularly as some of those seeking the inquiry are now in ill health or elderly.

"It is disappointing that they feel it is necessary to launch a judicial review," Mr Whelan said of the charities. "These organisations seem to have an issue with all of this coming out into the public domain."

A Scottish Government spokesman said: "Ms O'Brien's appointment has been received positively by many people, including survivors. She is an experienced advocate whose considerable knowledge and expertise was an important consideration in making this appointment.

"We are confident that her appointment is sound in terms of the Inquiries Act and that she will lead a fair, thorough and honest inquiry."