Horne said, though, that nothing in the law — and nothing in his opinion — appears to limit the ability of the Legislature or even cities or counties from enacting their own bans on the devices.

A 2006 voter-approved law makes it illegal to smoke in public places, offices and restaurants. It also requires hotels to designate at least half their rooms as smoke-free.

Horne said the key word here is “smoking,” which he said is limited to “any lighted tobacco product.” And he said that the dictionary definition of “lighted” involves setting something on fire.

“All sources of information on electronic cigarettes indicate that there is no fire or ignition involved in their use,” Horne said. Instead, he said e-cigarettes use a battery to generate heat — which, in turn, converts the liquid nicotine to vapor.

Potentially more significant, Horne noted that the ballot measure listed as its intent to protect people from “the health risks of breathing secondhand tobacco smoke.” And since there is no tobacco smoke, he said, e-cigarettes are beyond the scope of the law.

Horne also pointed out the 2006 law does not apply to other forms of tobacco use, like chewing it.