Re HA  EWHC 1068 (COP),  MHLO 67
"This case comes before me for directions today. The person whose best interests have to be considered by the court is a HA. The Official Solicitor now acts for her as her litigation friend and in that capacity has continued an application under s.21A of the Mental Capacity Act 2005 (the Act) that was instigated before his appointment."
Thanks to Alex Ruck Keene (39 Essex Chambers) for providing the judgment.
Possible Bailii link (not there when checked last night, but might have appeared since)