Parliament, and the much-touted PM's questions is supposed to hold the government to task. If the PM can lie to Parliament on a regular basis without any action, are there any standards worth talking about? In US terms, if an elected government, with the collusion of the judiciary and a supportive media, can ignore the constitution without any action against them being possible, are there any standards remaining? Here in the UK, the media have already tried to intimidate the judiciary by labelling those judges who were against the government's abuse of Parliamentary norms "Enemies of the people".
Enemies of the People (headline)
NB. This was 5 months after a UK politician had been assassinated on this issue.