I) Definitely read prior to arrest.
From the indictment (post 1) they read the emails prior to June 8 - they got the PO box # from the emails and served a subpeona on that date to get the subscriber info for that PO box.
OSOCA was still in business and the DEA placed an order with him on July 25.
So they definitely had access to decrypted emails prior to his arrest and possibility of cooperation.
That leaves in decreasing order of probability:
-1) keystroke logger
-2) diggers brute force attack on a weak passphrase (hadnt thought of that

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-3) compromise of Hushmails implementation of PGP.
if anyone knows of Hushmail having an independent auditors letter or Crypto community having oversite access to THEIR SOURCE and THEIR IMPLEMENTATION of PGP post up a link.
Lacking the above, nothing would stop Hushmail from installing a backdoor (perhaps at the "request" of USA or Canada post-9/11), and no one would ever know.
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-4) The possibility of cleartext email between OSOCA and GLP is out because GLP was on Hushmail as well.
II) Is this sentence in the indictment a hint? ->
".....Hushmail is a free encrypted email service that CLAIMS to secure the privacy security and authenticity of emails sent and received by its users....."
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