The legal doctrine of "fruit of the poisonous tree" is fairly basic in its premise: if the information being used in a case was obtained through illegal means, then any other information gathered via that illegal action is also tainted by the poison from the initial illegal action.
This has been used in any number of criminal cases in the past. One aspect of this which gets a lot of press is where you have a confession given by a criminal defendant who has not been Mirandized prior to speaking with police officers, and the question then becomes whether or not a warning should have been issued and, if so, whether or not the confession stands or has to be discarded because Miranda wasn’t properly followed.
In the case of the Administration having the NSA do domestic spying without first getting warrants as required by FISA, the question becomes whether or not a particular defendant was identified via an illegal wiretap. If that is the case, then any subsequent surveillance of that defendant could be declared tainted as "fruit of the poisonous tree" by the Federal courts. Any investigative work that stems from an illegal warrantless surveillance can be tainted.
When you think about how many cases that could be, the cost and time involved in sorting all of this out is staggering. And this doesn’t just involve terrorism cases. For example, how can a drug defendant know whether he was identified via regular surveillance or via an illegal NSA sweeping wiretap that just happened to pick up his conversation with a supplier in Jamaica? And as defense counsel, how do you determine which cases need further investigation and challenge — and how do you adequately protect your client’s legal rights against a secret national security program, albeit an illegal violation of FISA?
As a US Attorney, how ticked are you that your office is going to have to devote so much time to responding to these motions based on piss poor choices by this Administration, who true to form failed to consider the real world consequences of their actions on the whole of the government? Especially given the fact that the FISA laws give more than adequate emergency allowance for surveillance for 72 hours prior to obtaining a warrant — and the Preznit couldn’t even follow that simple law?
How this will ultimately shake out is anyone’s guess at this point. Given the secrecy of the surveillance programs involved, it will take quite a bit of digging to ascertain who may or may not have been surveilled improperly, and who may or may not have standing to bring action through the courts.
However things move forward, one thing is certain: pressure needs to be applied to the Administration to allow more sunshine into its dark corners. Government functions much better when we have confidence and trust that some light is getting through, even in the more opaque areas — and that is especially true for an Administration which has operated in so much darkness for far too long.
Some good resources for information on this:
– Washington Monthly’s Steve Benen.
– TPM’s Ward Report.
– SusanHu’s take at Booman.