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I would be fairly confident that you're not going to have a reasonable expectation of privacy with Twitter. With Facebook you might, because you can restrict who can see your site. The fact that I have a Facebook page is not something I can expect to be private. But the content, the fact that I have an album that only my friends can see–there's more expectation to be private.

The “reasonable expectation of privacy” is the test you apply.

Business communications–the company can access that. Contrast that with when I'm out to get a burrito for lunch, and on my phone, I tweet, “Out to get a burrito.” The company is not going to have a right in most cases to access that, because that's a personal communication on my time, on my equipment. Obviously the challenge can be: What if I tweet “Out to get a burrito” but on my company BlackBerry?

I use LinkedIn to validate people I'm interviewing. They told me they did a great job at X company, so I check who I know who worked there to back channel. That's legal–I put it up there so people can see.

But Facebook–[what if] I have some things that I've put up there that no one can see? They happen to show damning things. Someone pretends they are a long lost friend to gain access to it. It depends on why they're doing that, but I'd argue you have a pretty good case you're not allowed to do that.

Let's say conversely, I have my picture next to my name [on the basic listings section of Facebook]. Let's say the picture is me smoking a joint from when I was in college. A potential employer happens to search for me on Facebook and doesn't hire me based on that–odds are they're going be in the clear because I don't have an expectation of privacy with my picture.

The thing [in-house counsel] need to be reminded of: The rules evolve. We're just now getting to the point where we have understandable rules for email. Twitter? Forget it. By the time we have case law for Twitter and MySpace, we'll be on the on to the next thing.