Whether you believe it or not, there is a reasonable explanation for this in the opinion which doesn't require SIGINT magic, just fairly boring detective work.
It's possible, but I wouldn't say it's probable given that the agents seemed to know to search certain emails in order to gather material for a warrant after the fact.
If they had detective work in hand at the time of seizure which demonstrated the content of these emails, they'd have been able to get a warrant for the search on that basis.
> It's possible, but I wouldn't say it's probable given that the agents seemed to know to search certain emails in order to gather material for a warrant after the fact.
They didn't search "certain emails", they searched all of the emails on the laptop. It's not improbable that there would be interesting evidence in someone's email after a trip when you expect they will have been up to no good, and it's not improbable that a broad keyword search over those .pst's would find something.
> If they had detective work in hand at the time of seizure which demonstrated the content of these emails, they'd have been able to get a warrant for the search on that basis.
Yes, but they evidently didn't think they needed one: the dominant culture the agents were working in seems to say that this constituted a reasonable search, and that applying for a warrant after the fact was proper - that is the real problem here, and the one the judge is picking up on. The opinion describes this: they had enough warning of the guy's trip that they could decide whether to seize the laptop on the way into the country or on the way out, but decided on the latter to give the guy a chance to generate incriminating evidence, because they didn't think they'd catch him in the act otherwise.
Seriously, this looks more like an everyday process that's evolved in a bad direction than parallel construction. They weren't expecting to have to defend this search procedure.
