It was, I think, an extremely well made drama.
It was quite shocking to see what transpired in the eventual criminal trial which was manipulated in such a way as to make the not guilty verdict - to the very serious allegations of incitement and conspiracy to murder - an inevitability. Thorpe did not take the stand and so was never questioned on any of the issues. That was, of course, his prerogative but what was almost difficult to comprehend was the way in which the Judge got away with, in effect, rigorously advocating on behalf of Thorpe.
I think it was pretty clear from the documentary that followed the dramatisation that the establishment certainly closed ranks and hid information in order to protect one of its own. Being a homosexual or engaging in any other sexual activities that at that time were considered improper, did pose security risks. This had already been demonstrated in other cases (eg Vassell being blackmailed to spy for Russia) and so people like the Home Secretary were, it appears, in dereliction of their duty.