In my personal experience, there were one or two in a year. The last are more common. In any event, this is not important because the crisis does not depend on whether the basis is true or false but rather on the impact that it causes in the public opinion. Each medium of communication gives some explanation. This sector of the public only reads headlines.
Thousands read only the front page of newspapers hanging on the board in front of newsstands.
The problem is that this crisis demands first of all a great deal of time and effort. First comes the gathering of all published news on the matter, then the necessity to obtain verified information that responds to the questions of whether it is true that he was an employee, and if so, what responsibility did he have, what connections did he maintain with other employees, etc. The management of files is slow. But none of this is important. The national and international public already have the image of a trusted personal counselor or advisor of the Prime Minister who has been caught in the act of smuggling drugs with an identification card that identifies him as such.