re: Are brass knuckles and collapsible batons legal to carry in LA?

Best weapon (other than a handgun ) that you can openly carry is a walking cane with a crook wide enough to hook around someone's neck. Legally, it's a medical device, and due to restrictions in HIPAA, not even TSA nor police are allowed to question your need for such a device. I've carried them on board airliners without a second glance. In fact, they usually ask you to move to the front of the boarding line.

Get one made out of a solid hardwood like hickory.