John Major prorogued Parliament in 1997 to avoid the “cash for questions” scandal being debated before the general election which he called immediately after the period of prorogation – thus adding a further five weeks whilst Parliament was dissolved. There was no Fixed Term Parliament Act then!
Yet he has joined the action against Boris Johnson’s prorogation. So Major is a thorough-going hypocrite – as we all knew before!
At this time of the year Parliament usually goes into recess for the party conferences. Whilst in recess Parliament can be recalled at any time( as it can be during the Summer
holidays). But, once it has been prorogued, Parliament cannot be recalled until the period of prorogation is over. So by adding some days to the usual party conference season, the prorogation means Parliament is effectively out of action for over a month until it ends. Normally prorogation is quite a short period to allow for a new session of Parliament with a Queen’s speech announcing a new legislative programme. That is what Boris Johnson claimed as his motive for prorogation. The Scottish court took a different view, holding that it was a ploy to “stymie” parliamentary debate on Brexit.
The Scottish judges opinion (without hard evidence) interpreting Johnson’s thinking. They are making it up to suit their prejudices. One suspects they are Common Purpose.