So... what's our counter to this? We can layer up with more armor. We can bring more sticks and bats.
Here is California's Knife Law. Now I'm not suggesting bringing knives of our own. Just leaving this up.
http://www.shouselaw.com/california-knife-laws.html#1
- Knives that may be worn openly, but may not be concealed
California's laws against carrying concealed dirks or daggers is set forth in Penal Code 21310 PC. Penal Code 21310 makes it a crime to carry a concealed knife that is capable of inflicting significant injury by stabbing. These knives -- called “dirks” or “daggers" -- may not legally be carried concealed on your person. The prohibition covers knives tucked into a waistband or other article of clothing. It also extends to knives carried in a purse, pocket, or anywhere else under your control. California's has an “open-carry” law, however, for dirks and daggers. Dirks and daggers may be carried openly in a sheath -- if the sheath is worn suspended from your waist.1 The terms “dirk” and “dagger” mean the same thing under California law.2 They are any knife capable of ready use as a stabbing weapon that may inflict great bodily injury.3 The definition of a dirk and dagger is quite broad. In addition to knives such as daggers and stilettos, it can apply to such seemingly innocent items as: chef's knives; ice picks; knitting needles; and scissors. Carrying a concealed dirk or dagger on your person is what is known as a California “wobbler” offense. A wobbler can be charged as either a California misdemeanor or a California felony, in the prosecutor's discretion. If you are charged with a misdemeanor violation of carrying a concealed dirk or dagger, you could receive: up to one (1) year in county jail, and/or up to a $1,000 fine. If you are charged with a felony violation of the law, you could receive: 16 months, two (2) years, or three (3) years in county jail, and/or a fine of up to $10,000.4
- Knives that may be carried either openly or concealed.
Certain knives may be carried either openly or concealed -- unless the blade is exposed and locked into position. These include: pocket knives, non-locking folding knives, and other folding knives that don't meet the definition of a switchblade. 5 If the blade is exposed and locked into position, an otherwise legal folding knife becomes a dirk or dagger under California law. In such a case, it must be worn openly in a sheath suspended from the waist.