Freedom of thought and speech comprise something akin to an absolute rule - everyone is entitled to think whatever they want to think - and a series of relative rules - everyone is entitled to express those opinions in public, at least according to the context of this speech and its impact on other citizens.
Suella Braverman has helpfully put her career on the line (I'd have to say hopefully too!), in order to demonstrate this.
She clearly has some views on the standards being applied by the Met. She is entitled to them. She may or may not be right. But as a member of HM’s Government, Home Secretary no less, she (probably) ought not to be expressing them in the media in the manner she has done.
If the UK Government is saying out loud that it cannot actually control the justice system, then it is more or less in the same situation as its equivalent in Guatemala.
And we don't really believe them either.