During my time in gaming both before and after I worked in casinos then I have heard of numerous cheating attempts with most of them being blatant silly attempts that were doomed to failure and probably did. But one such case that I heard about but never found out if this actually came to fruition involved placing an invisible resin type substance into certain numbers of a roulette wheel.
This substance hardened like varnish but was clear to the naked eye. What this meant was that the substance could be applied to certain numbers without it being visible. But the peculiar characteristics of this substance were such that it recorded drastically different bounce to the other non applied numbers.
So if you applied it to the red numbers and not the black numbers then it would be perfectly possible that the ball would stand a far greater chance of coming to rest in one or the other due to the differences in bounce. The only problem was in how to apply this substance to a roulette wheel undetected. This would almost certainly need to be done from the inside from someone who not only worked there but who worked after hours or who had access to not only the casino but also the CCTV cameras as well.
There are several people who work inside all casinos who have this sort of function from general managers to managers to security staff and receptionists. So it is possible to have an inside job done on a casino. If you can overcome these two factors of getting the substance and then someone working on the inside then a casino would be very vulnerable to being hit in this way.
