I find this a bit concerning. Catching bad guys is all well and good but I wonder whether the various governments are overreaching. Selling a bugged phone to a known criminal is likely fine (cite: The Wire). But is it acceptable to sell a bugged phone to unknown/unidentified/random people and then use the phone's communications to determine if the owner is a crook and the owner's identity? The sole basis of suspicion…
>Step 1: Confirm known bad guy has phone through some other means.
>Step 2: Decrypt phone messages of known bad guy. Confirm they are criminal activities.
>Step 3: Note all previously unknown phones that exchanged criminal messages with known criminal.
>Step 4: Those phones are now considered belonging to known criminals. Return to Step 2.
Now, its totally possible they were just saying “someone bought a phone through TOR, they are probably bad so we can decrypt their messages” but that doesn’t have to be true for them to have worked their way through this criminal network.