Re: Either that or
"Although there's BTC in the story, I doubt they got her by tracing the transaction itself."
I expect nearly all BTC transactions to be inherently traceable based on the public nature of the blockchain itself. Even doing everything over Tor and moving between different sites unconnected to himself didn't keep Russ Ulbricht out of prison. He was arrested in a public library in such a way that his laptop was kept running, enabling its secrets to be made available for law enforcement. Tor also has its vulnerabilities including the fact that those who surveil its use are likely to be running an interestingly proportion of the nodes.
Biting the hand that feeds IT
