A code of conduct is absolutely required. My local hackerspace has a rule about proper footwear because some "functioning adult" didn't think he needed to wear

A code of conduct is absolutely required. My local hackerspace has a rule about proper footwear because some "functioning adult" didn't think he needed to wear shoes. On a shop floor with metal shavings. That's a liability risk no one wants to deal with. And "accidentally" dropping a 5lb hammer on the guy's toes isn't a good solution. As far as combating bully, tribalism, and harassment. A code of conduct isn't effective unless it's enforced consistently. My local hackerspace has had to remove people. It's been effective. Those people are no longer a part of the community and as a result, the hackerspace is safe place late at night.