Occasionally, people are banned from the facility where we hold the Seattle 2600 meeting. The Washington State Convention and Trade Center is a semi-private facility, operated by a non-profit corporation. While the Convention and Trade Center is owned by the state government, it is not legally a public place. The Dark Tangent, who started the Seattle 2600 meeting, learned this for us the hard way when he was arrested for criminal trespass at the third Seattle meeting (fortunately, he was not charged—although DT laughs about it now, it definitely wasn't funny at the time). Security is very familiar with the Seattle 2600 meeting, since it's been established for over 10 years now. After the Dark Tangent incident, they experimented with harassing us and watching us through new security cameras for a year or so.
For the past several years, in the absence of any reason to harass us, Security has been remarkably cool about the Seattle 2600 meeting. Nevertheless, if you behave like an idiot, they will ban you from the facility for a year or more, and can even have you arrested. This has, unfortunately, happened on multiple occasions over the years. Additionally, each incident further jeopardizes our continued privilege to meet at the Convention and Trade Center, so those responsible are likely to seriously annoy some very smart local hackers. Obviously, it's up to you whether this is wise.
If you don't behave like an idiot, you have nothing to worry about—you really have to piss off Security to get banned. Just be nice to people, stay out of the way of conventioneers, and clean up after yourself. That's all that the Convention and Trade Center staff asks—in fact, all they've ever asked—and we think it's pretty reasonable.
While it should be obvious to anyone with common sense, a list of reasons that you can be banned was requested. So be it. What follows are some examples of ways in which you can earn a ban, and possibly an arrest: