EU referendum, brexit and the aftermath

There is a belief that Cox said something along the lines that the backstop is a bad idea and will tie the UK to the EU in perpetuity as the backstop will be forever ongoing.

I don't really understand why the full legal advice is considered so important

Modern politics appears to be about dissembling, distraction, and the ability to reinterpret everything you do at any stage.

Publication of third party advice, on which you purportedly acted, means that you are pinned down and your narrative is restricted.

Or you could just be called out for making unsupported decisions for your own ends.

I don't really understand why the full legal advice is considered so important, but I suspect the fact that the Government is trying to withhold it suggests that there may be something there, although I'd be surprised if there were some kind of smoking gun. Or could it be a false trail to distract from something else?

Because the advice will contain a section called "how we could break the terms of the withdrawal agreement" or something similar - and I imagine the government doesn't want the routes that they have mapped out for screwing the EU made public.