All right, let’s talk about this thing called probable cause.

Probable cause is the standard needed to do various things, like arrest people, search their cars, and it’s used for exigent circumstances.

But probable cause simply requires a fair probability that something’s occurring. A fair probability, usually, of a crime being committed.

As the Supreme Court said:

“In dealing with probable cause, however, as the very name implies, we deal with probabilities. These are not technical; they are the factual and practical considerations of everyday life on which reasonable and prudent men, not legal technicians, act.”

— Brinegar v. United States, 338 U.S. 160, 175 (1949)

Why your prosecutor isn’t the best judge of probable cause

So when the Supreme Court says this is practical, everyday life type stuff, and not what legal technicians think, who are they referring to when they say legal technicians?

Lawyers.

The point here is that your prosecutor is not the best barometer of whether or not probable cause exists, because you know things that they don’t.

And obviously, no disrespect to my prosecutors out there. But they’re immersed in the law, in rules of evidence and so forth. You’re immersed in the criminal world, trying to ferret out crime. So your perception, your training, your experience is going to be different.

We don’t look at probable cause from the comforts of a nice office with mahogany and leather-bound books. We look at it from the eyes of a police officer and their training and experience.

What “training and experience” actually means

Let me give you a great example of what I mean by this.

When I left law enforcement, the big wave of training was for human trafficking. You see it all over the place now. You go to the airport, human trafficking this, human trafficking that. You see commercials about it, public campaigns, ad campaigns, all kinds of stuff.

Well, I never took any human trafficking training.

As a professional instructor, I travel a lot. Over the years I’ve been through almost every major airport in this country and seen millions of people collectively. And I gotta tell you: I have never once seen human trafficking. I’ve never seen anything that says to me, yeah, that person might be the victim of human trafficking.

Now, I was in the Chicago airport one time and I went to the bathroom, and they had a poster on the wall that said be on the lookout for human trafficking. It had some text on it, but it also had a bunch of pictures, examples of what trafficking looks like.

One of the pictures was of a person cleaning a hotel room.

And I said to myself, oh snap, I have seen that person.

I mean, I don’t know what that gets us. We’re gonna call 911 every time we see somebody working in a hotel? But that’s the point. I don’t know what it looks like.

So I was teaching some officers that worked at the airport, and I brought this whole thing up. These guys are probably the ones most trained in human trafficking. That’s one of their bread and butters. So I asked them what they look for.

And they started rattling off all of these little things that seem very innocuous to me, but to them are signs of human trafficking.

That’s the point here. Sometimes your prosecutors are in the same boat. Like I said, you see dead people. You see things that other people do not see.

So when you see a hand-to-hand transaction, some people look at that and say, oh, that’s just somebody giving a homeless person money. And you’re like, no, that’s a drug transaction. And they say, really? Why? Because of X, because of all these factors.

So the point is, you need to describe that.

How strong does probable cause have to be?

Probable cause is not a stringent standard.

It does not require that the suspicion a crime has been or is being committed be correct, or more likely true than false. Rather, probable cause simply requires a practical, common-sense decision whether, given all the circumstances, there is a fair probability that contraband or evidence of a crime will be found in a particular place.

Those two standards come from Texas v. Brown, 460 U.S. 730, 742 (1983), which held that probable cause “does not demand any showing that such a belief be correct or more likely true than false,” and Illinois v. Gates, 462 U.S. 213, 238 (1983), which gave us the fair probability test.

So it’s just common sense. It’s not very high. It’s just a fair probability. Sometimes it’s more likely than not, but sometimes it’s not quite that strict.

A simple two-out-of-three test for probable cause

I have an easy test to apply. This came from a student in one of our classes, and I wish I knew the student’s name so I could give them credit.

The student basically said, hey look, this is a two-out-of-three test. It’s very informal. It’s not in any case law. But when I heard it I said, you know what, that is something I can relate to.

Do you have a witness?

Did the suspect say anything that implicates them? A confession like “obviously I did it” is probable cause. But we want some other evidence too, because sometimes people confess to crimes they didn’t commit just to get attention. Admissions count as well: yeah, I was in the neighborhood, but it wasn’t me. That type of stuff.

Is there any physical evidence? Clothing left behind, a shoe print that matches their shoe size, those type of things.

Two out of three. Very informal, just a best practice. Was there a witness, were there any admissions or confessions by the suspect, and was there any physical evidence.

Probable cause vs. beyond a reasonable doubt

Now I got a question for you. What minimum level of proof do you need to convict a suspect in court?

It’s not probable cause. It’s beyond a reasonable doubt. BARD.

Beyond a reasonable doubt is the legal burden of proof required to affirm a conviction in a criminal case. The prosecution bears the burden of proving that the defendant is guilty beyond all reasonable doubt. That means convincing the jury there is no other reasonable explanation that can come from the evidence presented at trial. The jury must be virtually certain of the defendant’s guilt in order to render a guilty verdict.

So it’s not beyond all doubt. It’s beyond all reasonable doubt.

If the glove don’t fit, you must acquit.

Whose job is it to build a beyond-a-reasonable-doubt case?

Who’s in charge of finding enough evidence for a beyond-a-reasonable-doubt case? Who’s in charge of getting all that evidence together in a package?

If you are a law enforcement officer watching this, you better point the finger at yourself. Because you are. It is the job of law enforcement to find enough evidence to convict.

And the reason I bring this up is because law enforcement officers have been raised from day one on a diet of probable cause.

But probable cause does not get you a conviction.

Probable cause simply gets you into the courthouse. Or, as my friends from the Las Vegas District Attorney’s office have said:

Probable cause gets you into the club. Beyond a reasonable doubt gets you into the champagne room.

We all want to get into the champagne room.

If you’re in law enforcement, you’ve got to stop thinking only in probable cause. You are a professional. You are a criminal investigator. You’ve got to think about the end game, and the end game is a conviction.

So if you give your prosecutor a case that is simply full of probable cause, fine, you’re legal. That’s a legal arrest. But don’t be surprised or shocked or insulted when the prosecutor dismisses that case on the merits, because you cannot get a conviction based off of that.

It’s your job.

Now, a lot of prosecutors in big cities have the luxury of investigators that work for them. They can call that investigator into the office and say, hey Johnny, do me a favor, there’s a hole in this case. The officer put a witness in here but the witness statement isn’t that great. Go get a better one.

That’s great, if you have those kind of resources. But there are a lot of cops out there working for prosecutors that don’t have full-time investigators assigned to their office. So they’ll send it back to you with a nasty-gram.

Now, who’s in charge of delivering a beyond-a-reasonable-doubt case? The prosecutor.

So the way I look at it, you’re in charge of giving enough lawfully obtained evidence to the prosecutor. Then your job is done. You’re a professional investigator. You’ve got it to beyond all reasonable doubt, here you go. Now the prosecutor is in charge of delivering that case on your behalf. They know the rules of evidence, they know how to select juries, they know how to make arguments.

That’s how this works.

Why would you ever make a bare-minimum probable cause arrest?

Usually you do not want to, because oftentimes when you arrest a person or issue a citation, the investigation is over. You’re done.

Sometimes you’re continuing. But sometimes you are permitted, constitutionally and professionally, to make an arrest when the case may not be going too far.

Let me give you some examples.

It handles the problem for the night

There are cops out there that have been to domestic violence calls where it’s just not the best case. There’s all kinds of holes in it.

Let’s say the husband is the primary aggressor, but the injuries on the wife could potentially be self-inflicted. She is not cooperating. She’s highly intoxicated. But your state requires an arrest. And you’re thinking to yourself, man, if I don’t do something tonight, I’ll be back in 15 minutes.

But you do have probable cause.

And after you make that arrest, after you write that report, you’re thinking, you know what, I’m going to expect a letter from the prosecutor that this case is going to be dismissed because it’s just really not ready for trial.

I want to let you know that that is okay.

There’s nothing unconstitutional, immoral, unethical or unprofessional about making that kind of arrest, as long as you have probable cause. And besides the fact that some states require these arrests. But as long as you have probable cause, it’s okay to have a motive other than getting a conviction, like preventing more harm that you think is going to come.

Search incident to arrest

Don’t forget search incident to arrest.

Sometimes cops will arrest three occupants in a vehicle because a stolen gun was found in the center console and nobody’s admitting to it. The driver is always going to be easier to arrest, because there’s a presumption they know it’s in the car. But the cop also feels the passengers are in on it.

So you arrest them. And oftentimes when you arrest these guys, whether it’s for drugs or a gun, you’ll find more evidence on their person to prove their guilt. A holster. An empty holster. A nine-millimeter cartridge in their pocket, or a magazine.

The passengers are saying those drugs in the trunk aren’t mine. You’re like, okay, look, constructive possession, you guys are all going to jail for it. And you arrest them and you find burnt tin foil in their pocket, an empty baggy of white crystal substance. These type of things help prove they were in on it originally.

You need to interrogate

And finally, you need to interrogate.

So you arrest them. You have the probable cause. You have the fair probability that they’re involved in the conduct. And then when you take them back to the station, or right when you arrest them, oftentimes these guys are like, all right, I’ll tell you the truth. I knew about it, but I wasn’t gonna sell it, I wasn’t using it. That type of stuff.

All right, so that’s probable cause.

About the author

Anthony Bandiero, JD, is an attorney and former law enforcement officer, and the senior instructor for Blue to Gold Law Enforcement Training. He has spent over a decade teaching search and seizure law to officers across the country. The above is an edited transcript of a Blue to Gold lesson, available on video here.

This is legal education, not legal advice. Standards and arrest requirements vary by state. Check your statutes, your case law, and your agency policy.

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