AIUI, he is now only allowed to oppose them in private (or leave the cabinet):

"All ministers, whether senior and in the cabinet or junior ministers, must publicly support the policy of the government, regardless of any private reservations."

https://en.wikipedia.org/wiki/Cabinet_(government)

Doesn't sound democratic. Hmm...

Depends on how you look at it. Remember that in UK, there's no concept of separation of powers - the Parliament is sovereign, and the executive (monarch excepted) derives all power from it, inasmuch as the Parliament chooses to grant it. And one of those powers is to set policy for the entire cabinet.

In a sense, UK actually has too much democracy, and too few [formal] checks and balances on the power of the elected legislature.

It's called Cabinet collective responsibility: https://en.wikipedia.org/wiki/Cabinet_collective_responsibil...

Well we could vote him out although that is unlikely as he is in a safe Tory seat.

Assuming you are in support of his former public position, I think you'd be shooting yourself in the foot by doing that.

We don't know his private position any more, and it may have changed. But I think it's quite likely that his opinion hasn't changed; he just isn't allowed to state it publicly any more. In this case, it would be better for supporters of this position to keep him in the cabinet, where he can at least have a private influence. Consider this: if we could get everyone in the cabinet to share his opinion, we wouldn't have a problem any more. We need more David Davises in cabinet, not fewer.

The MPs to vote out are all the ones who are publicly in favour of the Snoopers' Charter. We can be far more confident in having an influence in our favour this way.

There is no restriction on where you must live to stand for parliament- I encourage you to stand against him!

Although, I would concentrate on Theresa May herself (I considered doing this at the last election when all this was mooted but blocked by the lib dems, but I stood where I live instead.)