To beleive something that is totally unture as a result of something possibly misheard or even dreamt.
A Joe-Lie will become so engrained in their reality that they will insist theyre right and will make up false evidence to back it up.
Tom: Hey Average Joe, you ordered the tickets for the festival yet?
Average Joe: Yeah man, ordered them yesterday should be here soon
Tom: The tickets arrived yet?
AV: Me and Shane are sorting it tonight.
Tom: I thought you said you ordered them ages ago.
Tom: Another Joe-lie!