>> Using Wi-Fi for police and fire is a Really Bad Idea(tm)!
>
> Not at all.

Sure it's a bad idea. Police, fire and other emergency response units need
a reliable means of communication. You get a couple of file-sharing users
on and the whole thing goes to pot.

That is why the FCC assigned the 4.9 GHz spectrum, in 2003, known as the
'Public Safety' band.