QUOTE (Street Magic)
Because the UCAS and the CAS still retain major bits
of the former US Bill of Rights in their legal codes, methods
like mental probes and aura reading can’t be used to gather
evidence, since both violate Fifth Amendment prohibitions
against self-incrimination.
[...]
In the UCAS, spectral evidence (that is, evidence or testimony
provided by spirits) isn’t admissible in court, so magicians
can’t do things like summon up the spirit of a murder
victim to finger his or her killer—because there is no way to
prove definitively that the spirit in question is in fact the victim.
That doesn’t mean, however, that spirits haven’t been useful
to investigations in the past, and in many cases, ghosts and
spirits have led investigators to evidence crucial to convicting
a suspect of a crime.
Things like astral signatures are OK, though, and in the NAN or Amazonia things are far different.