That's what keeps exchanges from thriving, I guess. Buying and selling stuff with bitcoins is, at most, tax fraud *if* it does not get reported to the IRS. Same as buying and selling using US$ for what that's worth.
But exchanging money in an untraceable way for bitcoins, and then back, is kind of a big bright shiny red arrow pointing at the exchange service. I, myself, believe there's no such thing as "money laundering", only money that taxes weren't collected upon, but that's not the point.
What can I, if opening a small exchange, do to prevent being mistaken for a money launderer and still keep the anonymous part of the deal? I mean, tax-wise, I'm more than happy to report as profit all the local currency profit I make, and even report on the size of my bitcoin stash (though as a non regulated commodity, there's no way to accurately correlate their value to local currency). But how can I keep away from liability, if the service I charge for is used for doing unlawful stuff and I don't report on the color of underwear of everyone trading on my exchange?
Sorry for stealing the thread, feel free to tell me off