People often say that it is illegal to keep bees in one way or another.... "First, if they are in the US, it is illegal." Now I certainly agree that it is not a good idea. But where is this law...?
It's a state thing.
For instance, in Ohio it's reg 909.12:
No person shall keep or maintain bees in any hive if all frames and honeycombs cannot be readily removed therefrom for inspection or keep or maintain bees in any hive situated where adequate and efficient inspection is difficult, impracticable, or impossible. All cross-comb hives or domiciles for bees, from which the frames and honeycombs cannot be readily removed, are hereby declared to be a public nuisance.
If any owner is found using such cross-comb hives or domiciles, the director of agriculture shall notify said owner in writing to cease using them. If, after the expiration of one year from receipt of said notice, the owner has failed to cease using said cross-comb hives or domiciles for housing bees, the director may seize and destroy them without remuneration.