If you are ever involved in a use-of-force incident and are charged criminally, one of the things that you can be certain of is that the prosecutor will ferret out every controversial thing you have ever posted online.

He will use that information to paint you as a bloodthirsty, Rambo-wannabe who was itching to kill someone for their own visceral pleasure.

What you post on social media, what you wear, the public behaviors you exhibit, and potentially what others post can be used against you in a court of law.

Posts on social networking sites such as Facebook, MySpace, Twitter, Instagram, blogs, and other social media are regularly popping up as evidence in courtrooms across the country. Social media evidence has been a critical element in several recent use of force court cases.

Prosecutors and defense attorneys have learned that searching people’s social networking and combing though some of what they’ve shared with the rest of the world is often a veritable gold mine of information.

In several trials, a witness’ credibility was completely lost in a matter of seconds when the witness was presented with something inconsistent they had written in the past.

As an example, in the murder trial of Lance Tiernan, the prosecutor used photos and posts from Tiernan’s Facebook to show a jury that Tiernan liked violence. Tiernan had posted pictures on his Facebook of him wearing a T-shirt with brass knuckles and a notation that he liked the movie “Fight Club.”

During the trial, Tiernan didn’t deny the page was his, so the judge admitted the Facebook posting as evidence. Tiernan’s attorney said that denying ownership would have been a mistake because the jurors would have already known that a Facebook post showed a picture of Tiernan with brass knuckles.

According to the defense attorney, the jurors wouldn’t even have to look at the exhibit and if Tiernan denied that it was his Facebook account it would have made his testimony less credible.

Here is some food for thought. Many self-defense and firearms associated Facebook groups and the discussions in those groups can encourage participants to believe they are among friends and as a result post potentially imprudent comments.

Below are just a few examples of quotes that I have seen in Facebook groups discussing various incidents.

Should have killed both of those cockroaches.
Needs a bullet between the eyes!
Needs to be shot.
Put a cap in him.

So let's say you’ve been freely expressing your opinion concerning shootings and other use of force incidents on Facebook and other social media.

You also like expressive T-shirts and you still find the Marvel fictional character “The Punisher” fascinating. Now you are involved in a self-defense shooting and perhaps it occurred in one of the more “progressive” jurisdictions — like Travis County, Texas.

Let’s go a step further and say that the miscreants who attacked you are of a different race, that the surveillance cameras only recorded one view of the incident, and that view does not completely reflect what you were confronting face to face. The progressive population demands that the progressive prosecutor present the incident to a grand jury and you are now charged with a serious crime.

Remember, self-defense is an affirmative defense and can be a two-edged sword. To present an affirmative defense, you must admit that you did the act; however, you affirm that you were legally justified in doing so.

The prosecution obviously disagrees and will be attempting to demonstrate that your action was not legally justifiable and that you in fact committed a crime. If the prosecution is successful, your life has just dramatically changed.

Now, think about this real hard the next time you are typing something online. Would you want a jury hearing that you had previously said any of the statements above?

What if there was a racial difference between you and your attacker and your attacker just happened to be of the same race as the individuals whom you called “cockroaches” and said should have been killed in a Facebook post? How do you think the jury is going to view this and your T-shirt picture that says a bullet is faster than dialing 911 or the Punisher decals on your vehicle?

Given some of the behavior you see in today’s society, it may be your opinion that the miscreant in a video did indeed need to be shot. Regardless, is this really a statement you would like a jury to hear and for your lawyer to try and defend?

Before making a post on a social media site, think about how people might interpret your words. Even if you feel they aren’t negative or damaging, a viewer might disagree. Never post anything online that you wouldn’t want to own up to publicly.

It’s important not to expect your social media posts to stay private. Even so-called private posts made or exchanged on social media can come back to haunt you in court.

Plan accordingly when using social media accounts to communicate with others. Consider them a journal that anyone could pick up off your desk or bring to court as proof of your private thoughts and activities.

Since even innocuous actions can appear to be inconsistent with certain claims, expect social media to be used in court when it might give the other side an advantage.

Remember that social media posts can also be a type of evidence that you have a duty to preserve. If you are involved in a self-defense incident and then delete your social media accounts, this could cast doubt on your credibility and imply that you are trying to hide something.

Since social media is such an ingrained part of modern life, expect that it will become an even bigger feature in court cases in years to come. It is a very good practice to keep you social media posts benign and only include things you’d want a potential jury to see.

How you dress and present yourself can also have unanticipated consequences. Posing for a picture in from of your cool vehicle that is covered in Punisher decals while wearing a T-shirt that says “a 9mm is faster than 911” may have implications you would rather not have your defense lawyer try to defend at your trial.

"Smile, wait for flash" engraved on your pistol muzzle might be clever but . . . you get my point.