When I lived in VA, I learned to OC because (at the time) it was illegal to CC in a restaurant that served alcohol. Given the choice between going unarmed or just uncovering, I went with OC. That law has since changed, but it opened my eyes to a whole world I never knew existed. I OCed occasionally in MS before that ludicrous AG Opinion was published, and I expect to resume OCing on 1 July with more-or-less the same frequency I used to. I've never considered myself much of an "activist;" although I'm happy to make a 2nd Amendment statement and educate the public, that's not the primary reason I OC.
So to answer your question, obviously, legality is the overriding criterion. Beyond that, some of the criteria I use include:
- Clothing. Some clothing makes CC difficult (or at least uncomfortable), some makes OC difficult. I'll choose a carry mode based on how easy/difficult it is to conceal and draw. So far, I use only belt holsters (tuckable IWB or OWB) and I try to keep no more than 1 layer of clothing between my hand and the weapon. In winter, I may wear an OWB holster under my coat, which could mean I'd be CC outdoors and OC indoors.
- Location/type of event. In certain situations, I don't want to attract attention/focus or make people uncomfortable, so I'll CC. When it's somebody else's "big day," it's bad manners to disrupt or distract from that. (For example, say I was going to a college graduation* or a wedding. Notwithstanding the issue of clothing, I wouldn't choose to OC because it might distract people's focus from the occasion.)
- Requirement for vigilance. OCing imposes a greater responsibility to maintain SA than CC. Will I be in a crowded area, making it more difficult to keep track of everybody and requiring that I constantly "watch my 6?" Do I expect my attention will be elsewhere a significant part of the time (browsing a museum, shopping, etc.)? If so, I'll usually CC.
- Deterrence. I live close to the tracks, both literally and figuratively. When I take my evening walk with my wife, I typically OC so any of the "gangstas" cruising by know that we're not to be hassled. In this case, the deterrence criterion wins out over the others (unless it's jacket weather).
- Possibility of LEO hassle. If I don't want to risk a possible encounter with LEOs (be they well-meaning but ignorant, or not-so-well-meaning), either because I can't afford a delay or because the "scene" would seriously detract from my plans for the day, I'll CC. Otherwise, I'll consider OC. Given the recent changes to Mississippi law, I'm curious to see how well-informed the LEOs are starting 1 July.
These are just my criteria. Others may disagree.
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* Currently not legal to CC or OC on campus. Appears that OC would be legal after 1 July. Ditto for a church wedding.
