If you want to give a player a "N0 innocent", you can use an Informed Townie. We interpret that as being a different role from a Cop (although a player could be both).
Note that there is information you can go on. For example, sometimes players will claim at L-1. Before claims (or in a symmetrical/all-vanilla game), you have at least two other sources of information: scum already know who the scum are (thus you can sometimes pick up on a player's lack of curiosity), and scum will typically be trying to prevent their buddies being the D1 lynch (they may give up doing so at some point if it looks like they're doomed, a transition that's also possible to pick up on). Note that it's often hard to make use of this information
on
D1 – thus it's more commonly used later in the game – but that doesn't mean that it's impossible.