There's an awful lot of lay interpretation going on here.
Do not be mislead into thinking that
just because pulling a gun does not constitute the use of deadly force, you can do so with impunity; the distinction probably has more to do with the prescribed penalty than with anything else.
This is the Florida law:
790.10 Improper exhibition of dangerous weapons or firearms.--If any person having or carrying any dirk, sword, sword cane, firearm, electric weapon or device, or other weapon shall, in the presence of one or more persons, exhibit the same in a rude, careless, angry, or threatening manner, not in necessary self-defense, the person so offending shall be guilty of a misdemeanor of the first degree, punishable as provided in s. 775.082 or s. 775.083.
Missouri law reads almost identically.
The problem is, that's only the part of the code that pertains to weapons violations per se. There's also the law on assault and aggravated assault. The penalty for that is generally a whole lot more severe in all states.
http://www.flsenate.gov/Statutes/index.cfm?App_mode=Display_Statute&Search_String=&URL=Ch0790/SEC10.HTM&Title=-%3E2009-%3ECh0790-%3ESection%2010#0790.10
As TexasRifleman has pointed out, the law there specifically provides for drawing a firearm when
force is required to defend oneself.
The Arizona law was particularly draconian until recently. The CCW website advised that if multiple toughs were actually shoving you and making verbal threats pertaining to great bodily harm, you could not draw or show your gun or refer to it without risking a charge for aggravated assault. Thankfully that law has been amended, but it is still not a license to pull the gun unless it is necessary.
The law now states that the “Defensive Display” of a firearm by a person is justified “when and to the extent that a reasonable person would believe that physical
force is immediately necessary to protect himself against the
use or attempted use of unlawful physical force or deadly physical force.” “Defensive Display of a Firearm” includes "verbally informing another person that you possess or have a firearm available; exposing or displaying a firearm in a manner that a reasonable person would understand was meant to protect oneself against another’s use or attempted use of unlawful physical or deadly force; or placing your hand on a firearm while the firearm is contained in a pocket, purse or other form of containment or transport". Obviously the previous law could land you in a lot of trouble, wrongly.
http://arizonaccwpermit.com/2009/07...efensive-display-of-a-firearm/comment-page-1/
So--the OP had a couple of people 50 yards ahead of him slowing down and a couple of people behind him speeding up. He apparently felt uneasy, but was pulling the gun
necessary in self defense (as in FL); was force
immediately necessary to defend himself (TX); was the defensive display of the weapon
immediately necessary to protect himself against the use or attempted use of unlawful physical force or deadly physical force (AZ)? I wouldn't want to have to depend on successfully arguing any of those assertions.
If the foregoing justifications do not apply, is the issue one of improper exhibition (a weapons violation), or one of assault, or both?
There is apparently no such law on brandishing in Pennsylvania. But--could it be concluded that the OP's action put someone in fear of bodily harm? That could fall under the assault law. The potential penalty is such that it conviction could result in a lifetime prohibition of gun ownership.
Of course, if pulling the gun was justified--immediately necessary, as it were-- that does not mean that firing would then be required. An attacking thug might well readily change his mind at that point.
Best to consult a local attorney who is familiar with the subject at hand and to avoid trying to divine the law means or what what one might argue.
And also best to watch what one puts on a public forum.