TLDR: article gives no answer. There is an active, anti-terrorism case going on and the defendant asked for evidence about how the IP & traffic was confirmed to be host and the FBI doesn't want to release it's methods to the courts/public
This should kill the FBI's case, since illegally-obtained evidence is automatically inadmissable in court (cf. fruit of the poisonous tree). If the only way to obtain evidence is through illegal means (e.g. unconstitutional wiretapping), then the evidence is inadmissible. But as we saw in the Ross Ulbright case, judges can arbitrarily overrule that protection against illegally-obtained evidence.
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A "CALEA" warrant approved by a judge makes it legal for US citizens. Federal intelligence have abused the secret FISA process established by the Patriot Act after 9/11. Foreign subjects do not require a warrant under FISA.
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This should kill the FBI's case, since illegally-obtained evidence is automatically inadmissable in court
in a banana republic the fed can overrule everything
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Add even with the weakest cases the Feds get a 99% convection rate. It is ridiculous.
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Well if the guy is lucky they will drop charges instead of having to disclose