Gun mods and legal repercussions for defensive carry/use:

[fatherguidosarducci]

I realize this may have been beaten to death but I thought I would bring this up again as I recently modified both my p-01 and p-01 omega through CZ customs here in Arizona: hammer spring, recoil spring, lighter/smoother DA and lighter SA with a slightly improved re set. FYI: the p-07 definitely came out better-- now at 7lbs DA and 3.5 lbs SA.  The p-01 Omega still has some stacking and is roughly the same weights:  maybe slightly heavier DA at 7.5 lbs.   And yes, I realize there is more they can do with the standard p-01 than the omega version.  I spoke with Doug there at CZ customs quite a bit after taking hold of my p-07.   

In any case, I plan on both of these being my defensive firearms-- night stand, truck, hiking, and possibly IWB CC.

I've always been under the impression that modifications like this should not be a big issue if--God forbid-- I have to draw and fire this weapon on someone who is threatening my life or that of someone near me. I've read the views of proponents and opponents of gun modification, and recently came across an article that was very well thought out, and the comments that came back at the author were interesting.

https://www.concealedcarry.com/safety/should-you-modify-your-carry-gun/

Then there was this:
https://www.minutemanreview.com/custom-trigger-on-concealed-carry-gun/

It got me thinking quite a bit about this issue. So many people modify their guns, and I know it's not just for competition shooting/range toys. If they didn't, CZ customs and Cajun Gun Works wouldn't be so busy.
It raised the question-- yet again-- is it worth doing anything to a gun that is strictly and EDC/defensive weapon outside of changing out the sights and grips? Are you/we risking too much at the hands of a scumbag attorney looking to sue you on behalf of the person who was shot? I'm not as worried from a criminal liability standpoint as I am from a civil suit standpoint, at least here in AZ. 
And yet, if you buy a competition ready gun such as a CZ sp-01 competition model or the Shadow 2, how is that any different than what I did to my p-01 or p-07? If anything, those guns have lighter triggers.   

It's made me re think keeping my p-01 omega and perhaps going back to get a stock p-01 and just learning to live with the DA trigger, even though for me personally, the omega trigger system feels better with its reach for someone smaller hands.   
I would love to hear from anyone who has experience having had to fire their weapon, and if it was modified, and what type of ordeal they went through.

I've listened to Massad Ayoob on this topic and some others.   I feel like the guys at CZ customs deal with this daily and set their guns to maintain maximum reliability for defensive shooting purposes for what I've done to the guns, but when I hear guys like Ayoob talking about 4lbs being the standard for what may be considered acceptable, it makes me re think things.     Then again, I'm guessing there are some who love their Shadow 2's enough to make them their night stand guns.   

[NeedCZ]

I suspect that it leans heavily on the political leaning of your location and the particular DA in it. 

I personally recommend against any cosmetic customizations to the gun or holster that could be used to claim that you might have been looking for trouble during trial. e.g. Punisher skull grips, skull and crossbones, etc.  I've also heard the bullets that one used could be used against you, so no RIP or Zombie Killer brands.  Nothing that an a**hole lawyer could wave in front of an uninformed jury and go "oooh scary!".

Springs and hammers are boring technical components that look normal so probably fine IMO. FWIW

[Grendel]

Despite what Ayoob and others might say, there has never been a case where a justified and lawful shooting has been overturned or otherwise deemed unjustified due to modifications of the gun or the type of ammunition. Nor are there any laws which state what modifications are and are not lawful to make to your gun, providing you don't turn it it into an unlicensed machine gun or something. Even then, you would not be prosecuted for murder if you killed someone in a justified self defense situation using it, you would be prosecuted for having an unlicensed machine gun.

If the shoot is righteous, it matters not what implement you use to commit it, a race gun, a stock shotgun, or a legally owned SBR.

Modify away to your heart's content.

[Philipl]

The primary use for our EDC carry guns is shooting water moccasins at the house. At 10-15 yards that can be challenging with a 9mm. My wife and I need the smoothest action and best sights we can get so our CZs all have Cajun Pro packages

[alp3367]

 I've seen this discussion numerous times over the years. For mechanical stuff it's a non factor for me. If replacing or modifying something makes it better for the defensive purposes I'd use it for I'll do it, if not I won't. Having said that I run most of my guns stock (Though I'll add NS if they don't have them) with the addition of a light and optic on some. But that's because they serve my needs not due to any consideration for legal issues.

PS - Though I do agree that cosmetic changes are something different. Don't put a "Born to Kill" dustcover on your AR or skulls all over your pistol. Common sense.

[fatherguidosarducci]

Thanks for the replies so far.  I don't think there is a clear consensus and I'm not sure where Ayoob comes up with the 4lb accepted threshold for trigger pull.   
He sites LTT in one of his videos:  that he got his Beretta 92 from LTT, but if you go their website, they have options for lighter hammer spring options that lighten the SA pull to below 4 lbs in some of their guns.

Regarding putting cosmetic modifications on your gun, yes, that's just pure common sense-- or at least should be. 

Lightening the trigger pull in DA and slightly in SA makes the gun easier to use specifically for defensive purposes.  We all get that.   From a criminal standpoint, I don't think it will be an issue against a DA.  But if the family decides to sue civilly and hires a scumbag attorney, internal mods to a gun may set you up to lose that case if you listen to guys like Ayoob and the links I posted.   
I don't think that applies to grips and sights.

Just my $.02/concerns.

[Skookum]

I'm not sure where Ayoob comes up with the 4lb accepted threshold for trigger pull.

Just speculating, but I think a 4-lb trigger pull is the minimum for NRA  and Camp Perry bullseye competition.  Thus, the rationale is primarily sporting (no one will have a magic hair trigger), and secondarily safety (no one can pursue a potentially dangerous hair trigger).  There is nothing mystical about 4 lb, it's regarded as safe, not that lighter pulls can't also be safe.

[radagast]

Greetings !
    I'm no lawyer, and being from NJ has probably conditioned me to think in terms of "worst case scenarios"; but most of the discussions I see on this subject center on the "shot on target" aspect of the event.
    My main concern is how modification could be presented in the event of collateral damage, negligent, or accidental discharge. While this may slide by in criminal cases, it's bound to get challenged in subsequent civil proceedings.

[M1A4ME]

Trigger pull?

Did the gun go off on it's own or because a finger was on the trigger?  If a finger was on the trigger wasn't that because the shooter intended to shoot the gun?  If the shooter intended to shoot does it matter if the trigger pull is 3 lbs. or 5 lbs.? 

More "thought" by people who don't understand tools/mechanics/science/reality?

If, on one hand, they say we are responsible for every bullet and where it goes then wouldn't they want us to have an accurate gun easy to hit the intended target with?  Why would they hold someone responsible for working to insure the bullets their gun fires goes where they intended and not somewhere else?

More dim/lib/prog/socialist thought processes in the courts, the judges, the juries, the prosecutors, etc.

Sights, grips, optics, reliable operation, a bushing that make the barrel stay in the same in the front of the slide, a trigger that allows firing the gun without jerking/moving it during the trigger pull, all of those contribute to helping the shooter insure the bullet goes where it was intended to go and not into an innocent bystander.

Some people are just not capable of realistic thoughts.  Used to work with some before I retired.  A real drag, as they used to say.

[tomboyjr]

 I dont think common sense is the issue here. The issue is how a liberal DA looking to make a name for himself will paint a picture of a guy that was just waiting to shoot someone (even if it was justified).  He will be telling the jury how the gun was modified to fire 'easier'. And 'faster'. And to hold more bullets. And, heaven forbid if you are carrying handloads, how you made those bullets to me 'more powerful' and 'more deadly'.

 Personally, my carry guns are bone stock. I'd hate to leave my fate up to some gullible and clueless jurors that might believe the lawyers nonsense.

[double-d]

Personally, my carry guns are bone stock.

I feel this way too

To each their own.

[Gunnerdad80]

I swapped my stock barrel with a better one, flat trigger, and all my mags have extensions for higher cap. God forbid I’m ever in the situation, I want the best advantage legally allowable.

[crc4]

If you don't know the 5 elements of a legally justified self-defense action you're behind the 8-ball and any gun modifications are the least of your worries. These five elements are applicable everywhere in the US, regardless of state. One can bellyache about progressive DAs, ultra-liberal states, and other things that have no bearing on these elements.

While many shooters can give you specifications of every CZ ever made and the fps of most jhp 9mm ammo, they fail miserably when asked what constitutes a justifiable SD event.

Remember, 'Stand Your Ground" is not a law. "Castle Doctrine" is not a law. Both those doctrines merely remove the obligation of a defender to retreat. There is no Stand Your Ground or Castle Doctrine defense. They are part of the 5 Elements of Self Defense where one of the elements of "Avoidence" is waived and not required to prove (or the prosecutor to disprove) a claim of self-defense.

Here's where you can find the 5 Elements of Self-Defense.

https://lawofselfdefense.com/beginjourney/

Whether it's at a criminal trial or civil trial either the prosecutor or the civil lawyer can raise any issue that they want to further their case. Thinking that a non-modified firearm gets you off from either a criminal and civil trial is folly.

Unless the firearm can be proved to have been inherently dangerous by modifications (which one should not do, like a .25 lb trigger pull) there's no harm in modifications.

Again, what counts as a modification? Changing grips, replacing the factory sight, replacing the recoil spring, etc.? If the prosecutor claimed your changing grips made your actions legally unqualified as an SD event, that's easily defeated by a GOOD SD lawyer. (A good SD lawyer is not the lawyer who drew up your will, did your land deeds, or defended you from a DUI.)

If your SD event is within the 5 elements of a legally justified SD claim, the legal gun modifications reasonably done are almost moot.

[Gunnerdad80]

That five elements link you posted doesn’t work, just FYI.

[crc4]

Thanks. It's been corrected.