Political gambling has a very long and permissive history in the UK, and in that sense, the UK is unique among gambling nations. There are no specific laws preventing insider trading in political gambling, which is what Craig Williams’ ‘flutter’ looks like to many. 

While this case would be easy to turn into a rule: ‘MP’s should not be allowed to bet on political matters’, it is very difficult to determine the boundary between political actors and the public more broadly. Should unpaid political advisors be barred from political gambling? What about newspaper columnists? 

It matters whether Williams knew from the decision-maker when the election would be held because if so, he is trading on insider information, which opens broader legal questions not specific to gambling. How common it is to gamble based on such knowledge is very difficult to assess. Williams’ smallish bet will not have moved the odds, but it is not uncommon to see large bets moving the odds as knowledge of a big political decision diffuses through political circles. What counts as certain knowledge is similarly hard to judge, Williams may simply claim to have picked up the ‘vibe’. 

As far as betting market manipulation is concerned, it is more obvious when you see the odds of a candidate winning propped up by large bets that raise their credibility in the hope that their short odds become a story. But again, these are difficult to prove.