Short for Law Enforcement, it is often used when referring to firearms and related items which are, by law, only for use by the law enforcement community or the government. LEO == law enforcement only.

See for some cool stuff you can't have if you are a USian serf.

These items include:

Why? Because the government said so. No real reason not to allow civilians to own these. It's just another way the BATF wants to say "screw you!"

If I had a short barreled shotgun in 12 gauge which I had used to obliterate an intruder who was going to do me or my family harm, have I not, in fact, enforced the law? And how! Aren't all guns in fact only for enforcing the law or hunting or sport shooting? Otherwise it would be wrongful use of a perfectly good tool.

*These can actually be had by civilians, but only after passing through the eye of a needle, please read my guide on How to buy a BATF Class III item.