https://www.slab.org.uk/guidance/employment-of-counsel-expert-witness-unusual-work-or-unusually-large-expenditure-4/
In contempt of court first instance proceedings you do not need our prior approval to employ counsel but you will have to justify their use at the accounts stage where you instruct senior counsel or more than one junior counsel.
Where the proceedings are on appeal you must obtain our prior approval to employ senior counsel or more than one junior counsel.
Where you are instructing counsel in the Court of Session or High Court both advocates and solicitor advocates can be paid as counsel.
In contempt of court first instance proceedings you do not need our prior approval to employ counsel but you will have to justify their use at the account stage.
Where the proceedings are on appeal you must obtain our prior approval to employ counsel. Counsel must be a member of the Faculty of Advocates.
It is important that you are aware that there is no provision to instruct a solicitor advocate in any contempt of court proceedings before the Sheriff Court or Sheriff Appeal Court.
If you instruct a solicitor advocate in those courts we can only make payment at the prescribed legal aid rates for a solicitor and only where they are registered to provide the relevant form of legal assistance. We cannot make payment in accordance with the prescribed rates for counsel.
We will challenge any account entry which indicates that you have instructed counsel in circumstances where our prior approval is required for their employment.
Where unauthorised counsel has been employed we will not pay for any of the costs of counsel, including:
You must obtain our prior approval for the employment of any expert witness and for work of an unusual nature or likely to involve unusually large expenditure (for example, where the work is likely to exceed £2,000).
An application can be made for retrospective approval for the employment of counsel, an expert witness, for work of an unusual nature or, as the case may be, work likely to involve unusually large expenditure in circumstances where that employment or work would have been approved had it been applied for timeously and there was special reason why prior approval was not applied for.
It is very important to note that there is no scope for retrospective approval for work of an unusual nature or, as the case may be, work likely to involve unusually large expenditure.
You should refer to the Applications guidance for more information.