Why should you want to know? Just don't hang around with people that have a chance to get banned. If you'll get banned you've did something terrible, because ANet doesn't ban someone for a little thing
actually, i was curious because during all that rampant botting at seeker's passage (great fun to watch bots, by the way), i put some suspected bots on my friends list to see if Anet would later ban them.
a bunch of them are now always "offline" -- i was just wondering if they had been banned.
yeah... someone who is botting or exploiting will sometimes tell everyone (which is stupid) but sometimes tell nobody (which is smart) and even those who tell nobody have a chance of getting caught. I got a fellow in my guild who was regular for a couple months and hasn't logged on in 2 weeks, and another who hasn't logged on in a week.