Crashedmint says he doesn't ever put anything incrimininating in writin, which is of course wise, but also close to impossible.Investigations into bad things often focus on "who knew what when", so if you get a mail of the form:"I'm having a real problem getting sensible numbers out of the new risk reports"do you treat this as a s/w bug or a warning that they are just making up the numbers ?In general, you can only know if something is incriminating after the fan has been hit. A while back I gave evidence to the Parliamentary legal commission being billed as a "professional invader of privacy", immediately after the head of the UK's gay police association (my life is rarely standard).Being a hybrid geek/headhunter I explained that data retention policies like that of Google's mail system are largely irrelevant, since data is backed up to stable media, typically tapes. It's viciously hard to delete a single record from streaming tape and few people even bother to try these days.You can physically destroy a tape, but that's actually quite hard to do in an environmentally acceptable way and anything less than fire (or the mix of concentrated sulphuric acid, nitric acid and hydrogen peroxide I used to clean teflon (so I could get gold to stick to it)) won't reliably kill it all.When you "delete" a record in most systems, it usually doesn't even disappear from the disk, just gets marked as dead.You don't even need to do key logging, for a few $K you can upgrade your firewall in the way several banks are quietly doing in a way that will allow them to monitor your Facebook and other social media traffic. They didn't tell you ? Well, you didn't ask.