Ar 27 Mawrth 2019, cyhoeddodd yr Uchel Lys ei ddyfarniad yn yr adolygiad barnwrol a oedd wedi’i ddwyn gerbron gan Bernadette Sargeant, yn ymwneud â’r weithdrefn y bwriedid ei defnyddio i lywio’r ymchwiliad annibynnol o dan arweiniad un o Gwnsleriaid y Frenhines. Roedd yr ymchwiliad wedi’i sefydlu i edrych ar weithredoedd a phenderfyniadau’r cyn Brif Weinidog mewn perthynas ag ymadawiad Carl Sargeant â’r Cabinet ym mis Tachwedd 2017.
On 27 March 2019, the High Court handed down its judgement in the judicial review brought by Bernadette Sargeant in relation to the procedure intended to govern the independent QC-led investigation, which had been established to look into the actions and decisions of the former First Minister in relation to Carl Sargeant’s departure from the Cabinet in November 2017.