Well, that&#x27;s the idea behind &quot;parallel construction&quot; -- a clean evidence chain is built up in parallel. That one isn&#x27;t exactly inadmissible and there is no proof linking one chain to the other.<p>Furthermore, there are protective policies where public prosecutors are given the discretion to exclude evidence gained from &quot;confidential&quot; sources (eg: undercover cops) and that revealing such evidence to the public would negatively impact current&#x2F;future investigations. Such evidence can be revealed privately to the necessary parties (eg: judges), but I&#x27;m not familiar with these procedures.