What members of law enforcement are trained/allowed to lie, to whom, and to what extent?

A sworn affidavit would be.

I mean, it’s not like people haven’t been convicted based on false testimony.

A cop can misstate the strength of their case. That’s not normally considered a lie, and would be distinct from presenting falsified evidence.

So, while it might have been rude or distasteful, a cop can come up to a witness and say something like “look, we know your boyfriend killed that clown, so there’s no need to cover for him. But unless you want us to consider you an accessory after the fact, you better tell us all you know about where he was after the circus left town!”

The case of 16 year old Nga Truong is a real eye-opener. The videos from the interrogation are hard to watch:

‘Anatomy Of A Bad Confession’ - Excerpt 1
‘Anatomy Of A Bad Confession’ - Excerpt 2
‘Anatomy Of A Bad Confession’ - Excerpt 3

Let’s first define what we are talking about. Most arrests are made because of something that happens in view of the officer. I don’t know what the exact percentages are but many are mandatory arrests on domestics. For the majority of arrests it’s not from after seeking out who the suspect is. It’s not hard to arrest a drunk driver after they hit a tree. Then you have a large number of criminals that are really stupid. Finding out who dunnit and getting evidence against them isn’t hard. Because they are stupid. Then there are the crimes that are done by someone not stupid and/or lucky. There is no evidence so they are closed out quickly. The small minority of cases involve long investigations and digging for the truth. They make for good 20/20 episodes and movies but they are not usual business. An officer can easily spend his career without being a detective. By the nature of the job most are not detectives. In some departments it is a temporary assignment and in others it’s a permanent position. A road officer will by nature get arrests due to the type of calls they have to go on. But they can easily spend an entire career without having to do casework like is being discussed here. Everyone automatically goes to murder in their mind but shoplifting calls take up much more of your time.

As was answered before lying to me is not against the law. (Lying to the FBI is) No one would be held in contempt and it certainly isn’t perjury. Any charges that could possibly be applicable in certain specific situations are actually extremely mild misdemeanors and wouldn’t be much of a threat.

I just can’t see how stating “I can prove mmmiiikkkeee was stabbing the drug dealer in the alley behind the pornshop” when he was demonstrably pumping gas on CCTV in a different city would not be considered a lie… it’s a blatant lie, supposedly endorsed/backed up by the government.

However, I think I get the general gist of the answer to my question. Something like:

Law enforcement - and everyone else - can tell all kinds of lies to each other, and doing so in itself is perfectly legal 99+% of the time. How those lies will get interpreted by others and their effect after the fact is wide ranging too broad to sum up in a single answer. Maybe nothing happens, maybe the outcome is mildly (or hugely) influenced, or maybe someone loses their job or their freedom. It depends.

If I’ve made a mistake in that summation, let me know. Otherwise, thanks everyone for the time and insights.

Right. And the old way of looking at that would be that such a lie would cause no harm because if the boyfriend was really innocent, and the witness truthful, then the witness would say, “Look, I don’t know what you know or what you think you know, but I am telling you that he was beside me on the couch the entire time in question, so there is no way he did it” and would stick by that story over and over again because that is the truth and you can’t get someone to say something that didn’t happen against their own interests.

Modern psychology has done a very good job of showing why that old gut instinct is incorrect in many, many cases.

I probably shouldn’t have hedged my language. Cops can lie. Well, sometimes.

Cops don’t have to be truthful about why they are asking your girlfriend questions. Just spitballing here: Maybe they are just trying to determine how well she knows you, and so asking about something they know is untrue is a ruse to gauge her commitment to you.

At least in Florida, the police can invent crimes to get evidence that they intend to use for other reasons.

In reviewing this tactic, the court considered it in the context of whether the subsequent evidence was provided “voluntarily” - this is really the crux of the legal issue: whether the evidence that is obtained as a result of the lie was the result of unlawful coercion, or harmless puffery.

There are limits of course. Police can’t claim legal authority they don’t have.

And as noted upthread, promises of leniency are considered coercive, too.


I know guys who are patrolmen in small towns and villages. They can go years without making felony arrests.

When I retired from my first career as a Deputy Sheriff one of my buddies retired at the same time. He worked his entire career in Courts, mostly transferring inmates from the jail to the court room. He was a fully sworn, armed Deputy Sheriff, yet in 25 years he never made a single arrest nor wrote a single citation.

I worked courts for a bit once. Home by 4:30 every night, all weekends and holidays off. Yet I hated it. The monotony drove me insane.

I don’t know.

I think cops who might coerce as suspect to confess wouldn’t be doing it if they thought it was a false confession. They would typically be forcing the guy to confess to something that they (the cops) believe to be the truth.

It’s likely that once a guy confesses to something true that he’s less likely to back away from it later. More significantly, once the guy confesses, the cops would then ask for all sorts of details consistent with the confession. Many of these details would then be independently confirmed, which would both bolster the case against the suspect beyond the confession but also make the guy less likely to retract the confession.

In the case of Morin I mentioned earlier, it appears the police involved had a “gut feel” that he was guilty, so their complete focus was on proving this. Inconvenient truths were ignored (a common human trait) and facts modified to make them fit the desired narrative. it was not obviously a desire to frame a suspect they knew was innocent.

The same applied to the Canadian case of David Milgard. Perhaps it’s more instructive as similar to what happened with a lot of wrongfully convicted in the USA, except lacking the element of racism. He was a “type”, the nomadic hippie unemployed sort common in the 60’s and 70’s. he was in the area, so they assumed he did the murder and spent the rest of the investigation just trying to provide enough evidence to convict him, whatever it took. They intimidated his acquaintances, who did not know him very well so were willing to testify what the police told them to say rather than argue when the threat was they could be implicated.

The kindest thing to be said about this is that it was sheer laziness on the part of the investigating officers.

You learn almost nothing about law in school. And the cases that make the papers tend to be sensationalized and are rarely discussed in great deal.

Realizing how little I knew about the subject, I’ve been trying to increase my general knowledge of many things including law. It is actually quite reassuring that most of the laws make a great deal of sense. The judges often seem very sensible, and properly skeptical, and while I sometimes disagree they do a better job than the media might have one believe.

I’m sure law enforcement varies immensely from place to place, in terms of funding, duties and diligence - but most do a hard job reasonably well. Nothing is perfect, but many of the problems often seem to be systemic ones resistant to change - many laws are simply out of date; lawmakers often show little interest in needed reforms, including to ways of providing service.

I agree. To read a well-reasoned judge’s (or judges’) opinion is a fascinating view into the sort of reasoning the law takes.

As ofr police, I agree the majority are honest people trying to do a good job. The glaring exceptions (like Chauvin) are glaring because they are exceptions. The main problem is that they need to be better filtered out before “one bad apple” spoils the whole bunch.

I agree. Sure cops are trained to expect horses not zebras, so if a spouse is murdered, they look long and hard at the surviving spouse, and sometimes miss the stranger who did the killing. But the police do want to find the real culprit.

Right. And that is why all those “and this time, it’s personal…” cop shows/films bother me. If your wife/brother/ etc was murdered - you can not investigate that case. Everything you gather will be thrown out and stuff you touched will be tainted. The killer may get free.

I had cases. Lots of cases. And yeah they wanted the cases closed, and without too many staff hours on them. But most of my investigations were letting the business owner off with a written warning and agreement they would sign. Or I would refer my case to the FBI, etc. I had no powers of arrest so never made one. I was called into a few organized Crime Task force things, where I spent lots of staff hours- and my Task force always got a conviction- “99 counts of wire fraud and money laundering” :grinning:, but there was no reward for them, just my manager grumbling about all those staff hours and no closures. One of the FBI agents bought me a steak dinner after one conviction, so that could count as a reward, I guess.

I never had to lie. The FBI, DEA etc guys didn’t lie either. The numbers spoke for me. And you can’t intimidate a spreadsheet.

Here is an article that addresses this question head on:

It’s a clickbait slideshow.

From the Onion.

In other words, not the highest-quality citation ever.

Apparently, Virginia does not condone this practice any more.

Police in Virginia Beach repeatedly used forged documents purporting to be from the state Department of Forensic Science during interrogations, falsely allowing suspects to believe DNA or other forensic evidence had tied them to a crime, the state attorney general revealed Wednesday in announcing an agreement to ban the practice.

The Virginia Beach Police Department said in a statement that the technique, “though legal, was not in the spirit of what the community expects.”

So they admit while allegedly legal, using actually faked (forged) documents is not in the spirit of what law enforcement should be doing.

Maybe because a savy suspect would ask to watch it, and if you balk they know you’re full of shit? If the video clearly shows me holding a severed head, you don’t have much incentive to refuse me, but it’s a lot easier bluff about a video that’s cross town at the DAs office.

But that doesn’t explain why its not permitted, legally. A savvy suspect could demand to see the purported tape whether its in the interrogation room or across town.

I took Loach’s post to mean that it was against dept. policy, not outright illegal.

“Sure, you want to see the video? Just sit tight in this chair, we’ll go get it. We’ll be back in 10 hours.”