October Novel Prep Challenge

A little more detail... are law enforcement authorities involved and searching for clues on the identities of these people? Do they have identification (driver's license, etc.) to validate the aliases? Or is this less formal, like, say I run across someone on WDC and want to figure out who they really are, what steps would I take to track down their identities as a non-police member of the general public?

Cheers,
Michelle