the fbi very famously subpoena'd google for a backdoor to some guy's password lock on his phone.
The one where you draw the little dots together.
Let's not panic too hard, folks. Facial recognition is far away from being useful in positive ID situations. It's hard to break it all down, but getting a 100% guaranteed positive ID on someone is hard as hell.
If you go and say, murder your neighbor, and leave some of your own fingerprints in your own blood, you could absolutely get away with it.
If there is no reason to suspect you, they would have no reason to take your prints or a DNA sample.
If you haven't been convicted of an offense in the past, your prints won't be on file.
I don't want to super get into it, and I'm not god or anything, but see above, and google it. You can strap on all the tinfoil hats you want to, but when it boils right down to it, cases fall to the roadside with the perp literally right there, ready to go, because of incompetence, privacy rights, and straight up human error.
When you add in the lack of understanding the average officer of any organization, be it interpol, fbi, police or whatever, has for tech in general, and then throw in insane foreign currencies and CCTV facial recognition, well at that point you might as well start screaming enhance at your monitor and expecting it to sharpen a tiny image to perfect clarity. magically.
I spent a lot of time studying professional forensic science, got to know a couple fed agents who were teachers on their free time. Having nothing to hide, I was deeply inquisitive and attempted to be as challenging as possible.
I learned a lot.
1: see above. Backdoor to a password lock. subpoena. seriously. THAT HAPPENED.
2: For real, for IT pros, I was uh.... well I was very frequently embarassed for them.
Us guys here, some members here and such could really benefit these forces as additions to it, but at this point it's kind of a mess of misunderstanding and assumption both on the part of the public and the fed.
I know an anecdote isn't anything, at all, especially on the internet.
But seriously, let's try not to worry too much. Stop watching CSI. seriously, please. I'd send you LTC to stop forever. it's making EVERYONE stupid.
Seriously though. subpoena'd google.
I googled it because I really couldn't post it without it:
http://nakedsecurity.sophos.com/2012/03/16/google-subpoenaed-by-fbi-who-failed-to-break-into-pattern-locked-samsung-smartphone/They aren't magic, crime stopping wizards. Solve rates aren't great in this country, and I don't think the IRS is going to come after your balls for a couple hundred dollars piling into your paypal once in a while.
If you're super worried, pay taxes on it. If you're super against taxes, power to you. Find a way to cash out to direct cash, likely locally. The guy you sell BTC in person to.... well, he's probably not a secret IRS agent. and if he is, be like 'duh dude I'm totally going to pay taxes on this" and then what's he going to do? Maybe audit you? OK, fine, good luck trailing all the cash that came in and was spent straight away on beer.
ENHANCE.