Conadile

As far as laws went, it was remarkably simple and concise.

"No-one in the land may Conadile, per order of the Crown."

In the centuries since, while the society had slowly but completely moved away from the monarchy, the law stayed put, and had a surprisingly consistent use.

Because of it, at various points, it was used to outlaw the use of a specific drug, a type of music, a sexual practice, and, currently, most forms of online business the government didn't like.

It's amazing what one can achieve when one controls the only official dictionary manufacturer in the land.