[TeamMCS]

Indeed. Take last years raid on the bank vault in London. Turns out they had full recordings on their calls. Whilst it did implicate them, how did they have them in the first place? And more interestingly, why to such quality.

[toyg]

From what I understand, they were bugged after the fact.

There is still a bit of a jump (how did they know who to wiretap? It wasn't really reported, afaik), but looking at the biographies of involved parties, they're the sort of people who would have been prime suspects anyway, so choosing to bug them was probably not an improbable decision to take.

[andrewaylett]

They spotted one of them driving nearby in his own car.

http://www.bbc.co.uk/news/uk-england-london-35267787 about half-way down.