This argument throws out the baby with the bathwater, though. "Parallel construction" is how every investigation is conducted. Investigators start with hunches, and search for evidence that proves/disproves this hunch. Parallel construction happens any time an investigator takes evidence and tells a story with it.
It doesn't matter much if you construct an investigation while being led by information obtained outside of the chain of evidence - at least it doesn't matter with any other kind of information.
You say, "basically they use evidence obtained illegally to prosecute someone" - but that's not what they're doing. They're doing exactly the opposite. They're using the legally obtained evidence to prosecute someone, and taking guidance from the other data that can't be admitted.
Based on the information from the article, 40% of the time, this illegally obtained evidence isn't any help. The data you say they are 'taking guidance from' is illegally acquired and used (at least 40% of the time, but maybe as high 100%). That's indefensible.
"Current and former federal agents said SOD tips aren't always helpful - one estimated their accuracy at 60 percent. But current and former agents said tips have enabled them to catch drug smugglers who might have gotten away."
Your quotation marks are out of order, because I took pains not to say "basically they use evidence obtained illegally to prosecute someone". It's more subtle than that.
In cases where the parallel construction was successful, it was probably illegal, and the convicted can appeal.
In refutation of your general thrust that all investigations are like this and it doesn't matter[2]:
"Not all evidence gathered by a private investigator is legal, however. For instance if the PI breaks into a private residence, taps a phone, or uses a planted microphone or listening device in a private place, then in these cases such evidence is not generally admissible. That is because any conversations or activities done in private places, behind closed doors have a reasonable expectation of privacy."
one last edit, just in case you had any doubt about the chance of successful appeal, this is legal terminology so it has a strange name but it is worth reading:
You keep begging the question by calling it "illegally obtained evidence" which ignores the fact that it's not illegal to obtain, just inadmissible. There's a difference, and entirely defensible.
You literally said "basically they use evidence obtained illegally to prosecute someone". Whether you went back and changed it later is a different story, but I copy+pasted what you wrote.
And if you think this is how fruit of the poisoned tree works, you're sorely mistaken. What you can't do is break into a home, take evidence, and use that evidence.
What you can do is, while you're executing a warrant on a home for another reason glance at your suspect's mail, notice a piece of mail is from someone you investigated prior who claimed to not know your suspect, go find another link between those two people, and then use their testimony once you've gotten them to confess to knowing the person as a link in a legit evidence chain. This isn't "fruit of the poisoned tree", and is basically what NSA tips are.
You are correct, I am begging the question, the DOJ are investigating the question. Maybe they will find the DEA and SOD are acting illegally. Hopefully they will. Those who would defend the use of NSA data for domestic crimes are dangerously close to advocating for a police state.
I may have written that quote and edited out because it was wrong. Sorry about that.
I doubt I am mistaken about the poisoned tree though because a source of evidence that may have exculpatory evidence is being obscured. It may also be acquired illegally but that is obscured too.
Implicit in your reply is an admission that the NSA tips are being used.
"people aren't being snatched up off the streets because of the NSA's monitoring programs."
Do you still stand by this because now there's evidence presented to you that the IRS and the DEA have access to NSA tips through the SOD?
A statement from the NSA:
"If the intelligence community collects information pursuant to a valid foreign intelligence tasking that is recognised as being evidence of a crime, [it] can disseminate that information to law enforcement, as appropriate."
I think your example of NSA tips is rather convoluted, I prefer the NSA's statement above as it's pretty clear and leaves little to the imagination.
You're right when it comes to the investigation. If the DOJ finds that this parallel construction is illegal, then I would accept it as such. My gut says they won't (because of the example I gave), but I accept the possibility that I could be wrong.
I still stand by what I said regarding the lack of "snatchings". If a parallel chain of evidence can be constructed that leads to an arrest, that's not "because of" the NSA's monitoring programs. That's because there is a valid reason to investigate this person. The lynchpin is not the NSA's tip, it's the ability to find evidence against a person that is obtained according to the law. A "snatching" would be attributed to the NSA if the only evidence were to have been obtained through the collection of "information pursuant to a valid foreign intelligence tasking". And that's clearly got no evidence to support it.
There's two modes of operation, you seem to have the second in mind, and I am thinking of the first:
1:
a. NSA collects American national's "information pursuant to a valid foreign intelligence tasking". (this may be illegal, violation of fourth amendment rights, no supreme court decision)
b. NSA tip SOD (if 1. is illegal, then it follows it's illegal to pass on)
c. SOD instruct police force to stop and search for 'traffic violation' at time and place, obscure evidence trail. (DOJ investigating if this is illegal)
d. d:a) no evidence is found.
d:b) evidence is found, parallel construction begins.
2:
a. law enforcement agency DEA/IRS/SOD asks NSA to get foreign intelligence, because of investigation already underway.
other steps as above.
My problem is with the first mode. Given the first mode, do you stand by your earlier statement and:
"If a parallel chain of evidence can be constructed that leads to an arrest, that's not "because of" the NSA's monitoring programs."
See the NSA's statement re: evidence of a crime. If the first mode leads to an arrest it is by definition "because of".
In both scenarios I have a problem with d:a) where no evidence is turned up because it seems like a very unreasonable search to me.
It doesn't matter much if you construct an investigation while being led by information obtained outside of the chain of evidence - at least it doesn't matter with any other kind of information.
You say, "basically they use evidence obtained illegally to prosecute someone" - but that's not what they're doing. They're doing exactly the opposite. They're using the legally obtained evidence to prosecute someone, and taking guidance from the other data that can't be admitted.