lab laser...

is it legal to own a lab laser with a power over 5mw? can someone send me a link to the laws? if so, can you power it up outside your house?

Yes to own, no to use outside.

You can use it outside so long as the beam stays on your property. After about 10K feet up you get into class G airspace, you need a permit to do so legally.

So, shining it on your fence is OK. Anything else is not.