It's an interesting thought, @Kirschcherries and @Puzzledandpissedoff.
There were 2 statements made in February 2026, one before AMW's arrest and one immediately afterwards (on the same day). The first was from Buckingham Palace, the second a personal one from the King.
Both expressed clear support for the police. I had assumed that would include allowing access to police for any purpose. He certainly gave them permission to access records at Buckingham Palace. https://archive.is/CchRe
My assumption would be that the Senior Officers would ask permission of the King, but would also seek warrants from a judge to cover for any uncertainties.
I'm copying the text of each statement here (as much for me being able to find them again as for others to see).
09/02/26
The King has made clear, in words and through unprecedented actions, his profound concern at allegations which continue to come to light in respect of Mr Mountbatten-Windsor’s conduct.
While the specific claims in question are for Mr Mountbatten-Windsor to address, if we are approached by Thames Valley Police we stand ready to support them as you would expect.
As was previously stated, Their Majesties’ thoughts and sympathies have been, and remain with, the victims of any and all forms of abuse.
19/02/26
I have learned with the deepest concern the news about Andrew Mountbatten-Windsor and suspicion of misconduct in public office. What now follows is the full, fair and proper process by which this issue is investigated in the appropriate manner and by the appropriate authorities. In this, as I have said before, they have our full and wholehearted support and co-operation.
Let me state clearly: the law must take its course.
As this process continues, it would not be right for me to comment further on this matter. Meanwhile, my family and I will continue in our duty and service to you all.
Charles R.