[quote=@Kingfisher]
<Snipped quote by Leidenschaft>

There wouldn't be anything particularly obvious, but Mancini has been using Ultra-Jet which is something that can only be acquired from the Ghoul mob, who the Lazzari are supposed to be at odds with.
[/quote]

Well, Redding does have a lot of experience selling and running drugs, he'd probably notice something was off about the jet inhalers. Being an independent pimp and dealer between the giants of Reno would also give him the knowledge of who sells what.