Interestingly, the law states that no flag (either Swiss, cantonal, or municipal) can be desecrated if it is displayed by authorities, though no such limits are imposed in the private sphere. In other words, if a flag is flown in "official" capacity on August 1st, Swiss national holiday, and someone inflicts intentional damage to it, then yes, that is illegal. But if, say, football fans tear or burn the flag after a game because the Swiss team lost, this is perfectly legal.