Whilst MP's and Government Ministers are entitled to a private life, it is essential that all MP's are fit and able to carry out their duties, and represent the British people. MP's should be in full control of their senses and faculties when deciding legislation and taking part in votes, and while at work in Parliament, or their constituencies.
Why is this important?
Westminster is fast losing the respect and authority of the British people, This they must regain. We can no longer afford drunkenness and inappropriate behavior to be allowed in the Houses, and while they carry out their many other duties.