Can I Get a DWI for Marijuana or Edibles in Texas?

Hello everyone, this is Deandra Grant, and you are watching the Ask Deandra video series, in which we answer the most commonly searched questions about DWI in Texas. This video series corresponds with our blog series, and the link to the blog on this topic for today is down in the description.

Today’s topic is: can I get a DWI in Texas on marijuana or THC edibles? Let me first of all say yes, of course, but let me explain why. Especially if you have moved to Texas from another state, let me give you an overview of some of the differences.

Some states have what we call a per se limit on THC. What that means is, you’re very familiar, I’m sure, with the concept of 0.08 or greater. If you have a blood alcohol concentration or breath alcohol concentration of 0.08 or greater, then there’s a presumption that you’re intoxicated. That’s a per se limit. So the question then becomes, how can you create per se limits on drugs?

Well, in some states it is if they can detect any amount of a drug in your blood system. If they can detect any amount of THC, then that is per se intoxication in their state, which is quite frankly ludicrous. Ohio does that. I think Louisiana maybe does that. There are several states that have this very strange law, because having a detectable amount of any drug in your system does not correspond to it having any effect on you. It’s not like alcohol. So, very strange rules in some states.

Other states have what we call a presumption number. I believe Colorado’s is 5 nanograms. So if you have 5 nanograms of delta-9 THC in your blood, then that is a presumption that you’re impaired. Once again, that number is sort of pulled out of a hat somewhere. It doesn’t really correspond to what the science says about THC, but that is the rule in some states. And there are some states that have 3 nanograms as theirs.

Now let’s take a look at Texas. Texas does not have any per se numbers when it comes to any substance other than alcohol. What that means is the definition of intoxication in Texas is not having the normal use of your mental or physical faculties due to an introduction of a substance. That substance is most commonly alcohol, but it isn’t always alcohol. It could be a drug. It could be NyQuil. It could be heroin. It could be THC. It could be benzos. Whatever you take into your body that causes you to either lose the normal use of your mental faculties or the normal use of your physical faculties meets the definition of intoxication in Texas.

So without a per se limit for a drug such as THC, the state is left to try to prove the case through observations of the police officer, perhaps behaviors that you exhibit on video, driving behaviors, perhaps even statements that you make to the officer while answering questions there at the scene. They try to take the totality of the circumstances and prove to the jury, assuming you’re having a jury trial, that this number in your blood of THC and all this other evidence proves that you didn’t have the normal use of your mental or physical faculties.

I will tell you that it is more difficult for the state to prove these cases than it is for them to prove cases based on alcohol. Let’s talk a little bit about THC, which you may or may not know. I’m in an organization where we run a bunch of tests on people, and it’s been the same outcome every time we’ve done it. You take three people, and one of them is a novice user of THC, one of them is an occasional user of THC, and one of them is a frequent, like daily, user of THC, and you run them through what’s called the drug recognition program’s protocol, which is a 12-step process that specifically trained officers called DREs run people through, looking to see if they can give an opinion on impairment.

If you run folks through that under these circumstances, where you take these three different types of people and they haven’t done anything that day, they haven’t used any marijuana, and you have them run through the DRE protocol and you get results from all their various testing, and then you send them off to smoke marijuana, the same amount of marijuana over the same period of time, like for instance over lunch, and then you bring them back and you run them through the same protocol, you will see that the person who is a novice user, who has no experience with THC, will have impairment. It’ll be very obvious. The occasional user might show some signs of impairment, might not, but their impairment will probably not look as significant as the novice user. But if you take the person who regularly uses THC, they might even do better after lunch on the field sobriety tests and DRE evaluation than they did before. I’ve seen this over and over again.

THC is an interesting drug because it impacts people differently and people build up a tolerance to it. There are other drugs you can build up tolerances to, but THC is a pretty interesting one. So the person has their blood drawn because they’re suspected of driving while intoxicated on THC, and there’s some number of nanograms. Maybe it’s seven. Let’s just say seven nanograms of delta-9 THC in their system. You look at that number, and what does that number tell you? Well, it really doesn’t tell you anything unless you know what this person ingests on a regular basis, when was the last time they used any THC, and what do they look like on video.

They may look perfectly fine. They may get arrested for DWI because they had a burned-out taillight, got pulled over, the officer smelled marijuana, gets them out of the car and decides they’re arresting them for DWI, but the person doesn’t even look impaired on the video. We see this a lot on these THC cases, where the person on video looks very normal. That’s one of the reasons it’s very difficult for the state to prove these cases in some circumstances. Obviously, if we have a client that looks extremely impaired on video, then that might not be a case that’s going to trial, but you never know.

So that’s sort of where we are with THC in Texas right now. Is it possible in the future that our legislature might pass a per se number that leads to a presumption that you’re impaired at 5 nanograms of THC? Yes, but that has not happened at this point at the time that this video is being recorded, which is August of 2026.

I hope you find this useful. If you want more details on this topic, like I said, the blog link is in the description for this video. Thanks a bunch, and we’ll see you next time.