Per the American Knife and Tool Institute:

Chapter 45 “Weapons and Possession of Weapons” which is found within Title 22 contains provisions relative to knives. § 22-4504 provides that it is unlawful to carry, either openly or concealed, “any deadly or dangerous weapon.” Any knife can be such a “deadly or dangerous weapon” as discussed below.

Source

I heard there was a baseball game on the 6th, don't forget your equipment. If you bike there don't forget a bike lock and chain.

tons of keychains self defense ones that might be better if you are concerned.