SCA 1981, s 70 (and an equivalent provision for county courts in in County Courts Act 1984, s 63) enables the court to appoint assessors:
70 Assessors and scientific advisers
(1) In any cause or matter before the High Court the court may, if it thinks it expedient to do so, call in the aid of one or more assessors specially qualified, and hear and dispose of the cause or matter wholly or partially with their assistance.
(2) The remuneration, if any, to be paid to an assessor for his services under subsection (1) in connection with any proceedings shall be determined by the court, and shall form part of the costs of the proceedings.
FPR 2010, r 25.20 explains how this can be done. That either of s 70 or s 63 apply in the family court is not as clear as it might be. The assessor could be a person whose opinion – including decision-making – might assist the court. Their role in many ways would be similar to that of a jointly funded expert. The issue of costs remains (s 70(2) above); but so far as the court has power to award costs against a third party (SCA 1981, s 51(3)), perhaps it could order assessor’s costs from public funds (ie HMCTS).
(3) Attorney General
In H v L and R  EWHC 3099 (Fam),  2 FLR 162 Roderic Wood J and the Attorney-General arranged for an advocate to the court to be appointed for the father limited to cross-examine a vulnerable witness for the mother. That was dealt with under the Attorney-General’s Memorandum of 19 December 2001  Fam Law 229 (see eg Family Court Practice 2014 at p 2869: this memo remains basis on which the A-G deals with requests for appointment of an advocate to the court). A request comes to the A-G from the court. The memo with appointment if the A-G so decides (paras 3–8), and in particular it stresses that an advocate to the court ‘represents no one’ (para 4): his/her role is limited to that professionally adopted by him/her (ie not eg on instructions from any party). Request is made by the court to the A-G (para 9). It is for the Attorney General to decide whether assistance will be provided and on what terms (para 10).
Memorandum – Requests for the Appointment of an Advocate tothe Court(1) The memorandum hasbeen agreed between the Attorney-General and the Lord Chief Justice. Itgives guidance about making a request for the appointment of an advocate to thecourt (formerly called an amicus curiae).
(2) In most cases, anadvocate to the court is appointed by the Attorney-General, following a requestby the court. In some cases, an advocate to the court will be appointed by theOfficial Solicitor or the Children and Family Court Advisory and SupportService (CAFCASS) (see paras 11 and 12 below).
The role ofan Advocate to the Court
(3) A court may properlyseek the assistance of an advocate to the court when there is a danger of animportant and difficult point of law being decided without the court hearingrelevant argument. In those circumstances the Attorney-General may decided toappoint an advocate to the court.
(4) It is important tobear in mind that an advocate to the court represents no one. His or herfunction is to give to the court such assistance as he or she is able on therelevant law and its application to the facts of the case. An advocate to thecourt will not normally be instructed to lead evidence, cross-examinewitnesses, or investigate the facts. In particular, it is not appropriate forthe court to seek assistance from an advocate to the court simply because adefendant in criminal proceedings refuses representation.
(5) The followingcircumstances are to be distinguished from those where it will be appropriatefor the court to seek the assistance of an advocate to the court:
(i) wherea point of law which affects a government department is being argued in a casewhere the department is not represented and where the court believes that thedepartment may wish to be represented;
(ii) wherethe Attorney believes it is necessary for him to intervene as a party in hiscapacity as guardian of the public interest;
(iii) wherethe court believes it is appropriate for a litigant in person to seek free (probono) assistance;
(iv) where,in a criminal trial, the defendant is unrepresented and the advocate to thecourt would be duplicating the prosecutor’s duty as a minister of justice ‘toassist the court on all matters of law applicable to the case’;
(v) wherein a criminal case in relation to sentencing appeals there are issues of factwhich are likely to arise and the prosecution ought to be represented, or itwould be reasonable to ask the prosecutor to be present and address the courtas to the relevant law.
(6) In the first of thesefive cases, the court may invite the Attorney to make arrangements for theadvocate to be instructed on behalf of the department. In the second, the courtmay grant the Attorney permission to intervene, in which case the advocateinstructed represents the Attorney. In neither case is the advocate an advocateto the court.
(7) In the third case thecourt may grant a litigant in person an adjournment to enable him or her toseek free (pro bono) assistance. In doing so, the court should bear in mindthat it is likely to take longer to obtain free (pro bono) representation thanfunded representation. In contrast to an advocate to the court, a free (probono) legal representative will obtain his or her instructions from thelitigant and will represent the interests of that party. His or her role beforethe court and duty to the court will be identical to that of any otherrepresentative of the parties. Accordingly it will not be appropriate for thecourt to take such a course where the type of assistance required is thatprovided by an advocate to the court.
(8) In the fourth casethe prosecutor’s special duty is akin to an advocate to the court. In the fifthcase, in relation to appeals against sentence where the defendant isrepresented, it may be preferable to request the attendance of the prosecutor,who will be able to address the court on issues of fact and law. It would notbe proper for an advocate to the court to take instructions from theprosecuting authority in relation to factual matters relating to theprosecution. An advocate to the court should only be asked to address the courtas to the relevant law.
Making a request to the Attorney-General
(9) A request for anadvocate to the court should be made by the court as soon as convenient afterit is made aware of the point of law which requires the assistance of anadvocate to the court. The request should set out the circumstances which haveoccurred, identifying the point of law upon which assistance is sought and thenature of the assistance required. The court should consider whether it wouldbe sufficient for such assistance to be in writing in the form of submissionsas to the law, or whether the assistance should include oral submissions at thehearing. The request should ordinarily be made in writing and be accompanied bythe papers necessary to enable the Attorney to reach a decision on the basis ofa proper understanding of the case.
(10) The Attorney willdecide whether it is appropriate to provide such assistance and, if so, theform such assistance should take. Before reaching a decision he may seekfurther information or assistance from the court. The Attorney will also askthe court to keep under review the need for such assistance. Where thecircumstances which gave rise to the original request have changed, such thatthe court may now anticipate hearing all relevant argument on the point of lawwithout the presence of an advocate to the court, either the court or theAttorney may ask the advocate to the court to withdraw.
Requests to the Official Solicitor orCafcass
(11) A request for anadvocate to the court may be made to the Official Solicitor or CAFCASS (LegalServices and Special Casework) where the issue is one in which their experienceof representing children and adults under disability gives rise to specialexperience. The division of responsibility between them is outlined in PracticeNotes reported at  2 FLR 151 and  2 FLR 155.
(12) The procedure andcircumstances for requesting an advocate to the court to be appointed by theOfficial Solicitor or CAFCASS are the same as those applying to requests to theAttorney-General. In cases of extreme urgency, telephone requests may be made.In some cases, the Official Solicitor himself will be appointed as advocate tothe court. He may be given directions by the court authorising him to obtaindocuments, conduct investigations and enquiries and to advise the court. He mayappear by counsel or an in-house advocate.
LORD GOLDSMITH QC
THE LORD CHIEF JUSTICE
THE RIGHT HON THE LORDWOOLF