[adrianN]

And yes, if someone did commit a crime using my network the police might visit, but what better defense is there than the fact that I have an open wireless network? If I enabled wireless security on my network and someone hacked it, I would have a far harder time proving my innocence.

In Germany this defense wouldn't really help you much. You're (partially) responsible for the crimes that are committed over your unsecured network. It's called "Mitstörerhaftung".

[pyvpx]

I can attest as an American in Berlin -- Germans are VERY serious about their privacy. this is especially true when related to the network/internets.

[Tomte]

No, Mitstörerhaftung is a purely civil concept that does not -- and could never -- extend to criminal law.