Joseph Ruiz

Joseph Ruiz was born in Spain and raised in Houston, Texas. He and his wife of 6 years are expecting their first child in November 2019. He graduated from Vanderbilt University in 2001 before obtaining his JD from the St. Maris University School of Law in 2004. He began his career working in civil litigation before transitioning towards his true calling—criminal defense. He is a member of the Harris County Criminal Lawyers Association, the Texas Criminal Defense Lawyers Association, and the DUI Defense Lawyers Association. He has published articles on trial tactics in HCCLA’s The Defender magazine. Joseph tried 300 jury trials in traffic, municipal, and JP courts before moving into the state court arena, where he's tried over 40 cases to verdict. He has secured numerous acquittals and has obtained over 500 dismissals for his clients. Most recently, he secured a not guilty verdict in Harris County for a young man in a .16 blood draw/accident, which led to a .266 blood draw dismissal on the eve of trial the following week. Before that, he won a contentious trial in Brazoria County for a client charged with deadly conduct after accidentally shooting someone with an AR-15. When he’s not competing in the courtroom, he enjoys competing on the basketball court.

Persuading Jurors to Accept a Disconnect Defense

Overview of the Defense and Ground Zero

The DWI practitioner is familiar with the concept of the disconnect defense—the idea that if most, or all, of the evidence in a DWI case fails to match up with a really high alleged BAC (.16 or higher), there must be a problem with the reliability of the breath or blood result and the jury should, therefore, acquit the accused.1 While in theory this sounds like a feasible, logical, and commonsense defense, the reality is that persuading jurors to accept the disconnect defense is a monumentally difficult task. We lawyers spend countless hours attending CLEs, scouring treatises, expert witness transcripts, scientific peer-reviewed articles, appellate decisions, CLE materials, and the like. However, having a mastery of the legal and scientific concepts that arise in a DWI trial, alone, won’t be enough to get us there in disconnect cases. Specifically, we need to be able to take off our lawyer hats and put on our private-citizen hats in order to be able to effectively persuade jurors to reject the State’s purported science. We need to be able to connect with jurors on a basic human, visceral level in order to move them towards that NOT GUILTY verdict. This requires the dedicated trial lawyer to pursue a greater understanding of human nature, psychology, and the psychology of decision making.2 Combining knowledge of the psychology of influence and persuasion with the knowledge of the legal and scientific intricacies involved in a DWI case will give us all the best chance at success when we present our disconnect defense to the jury.

So why do we need to make this investment of time learning about things not directly in the legal or scientific arena? Look no further than the comments following our local news coverage of any criminal case, in general, and high-BAC DWI cases, in particular. There we will find incredible, unfiltered statements that should give us a sense of the pulse of our community’s jury pool. We can make the mistake of chalking this up to the interviewees being fanatics or internet trolls, or we can face the reality that these same folks are gladly appearing for jury duty, looking to further their agenda. If even one of these persons gets on our jury, our disconnect case likely just turned into a “connect-the-dots-for-the-state” case.

Ultimately, in order to persuade a jury to accept our disconnect defense, we’ve got to be selling it to the right jury, and by that I mean a group of individuals that will at least be receptive to our message, even if just for a limited window of time. Dr. Cialdini’s research teaches us that the best communicators capitalize on what he calls privileged moments for change in which an audience becomes receptive to a message before they actually experience it—“pre-suasion.” While we can’t hope to change a person’s attitudes, beliefs, or feelings about a subject, we can alter a person’s focus of attention just before requesting something from them, thereby increasing our chances of successfully persuading them. Let’s turn to how this concept can play out in jury selection.

Voir Dire—Discarding the Role of Underdog by Establishing Rapport, Trust, and Credibility

Prior to beginning our portion of the voir dire, we are underdogs to say the least. Heading into trial on my .161 blood draw with a T-bone accident, I knew it would be an uphill battle no matter how favorable the video.3 Because of the high BAC and accident, we aren’t supposed to win a case like this, which means we really have nothing to lose. But we have to have the mindset that we are absolutely going to win. I suggest getting into the prosecutor’s head leading up to the trial date. Check in to see what the court’s trial docket looks like ahead of time. Let the prosecutor know that you’re really excited to try this case. Put them on their heels a bit. They’re the ones with all the pressure to win.

Listen extremely carefully during the government’s voir dire. If they in any way misstate the law, we should not hesitate to object. If the judge sustains the objection, the prosecutor’s credibility has taken a big hit. Whether their misstatement of the law is incompetence or a ploy to gain an unfair advantage, the potential jurors will not appreciate it. Meanwhile, we’ve ele­vated ourselves as credible authorities on the law, shrouding us with more persuasive power and appeal. At all times during the trial, defense counsel must strive to be the most credible person in the courtroom.

We’ve all seen the State’s first PowerPoint slide. It has their fancy seal and it says “The State of Texas vs. John Doe—DWI.” We need to battle for that authoritative credibility. Our slide shouldn’t mention the State of Texas at all. It should instead say “The Jury Trial of Mr. John Doe” and have our firm logo on it. I believe this at least places more of their focus on themselves, our client, and us instead of it being all about the State of Texas.

To establish rapport, we should talk like a prospective juror rather than like a lawyer. For example, there is no need to impress potential jurors with legal jargon like “voir dire.” We should simply refer to it as “jury selection” when conducting our voir dire. When it’s our turn, we should take a brief moment to re-introduce ourselves and our client, placing both hands on the client’s shoulders, letting the panel know that we are honored and proud to be here representing Mr. John Doe.4 Impress upon the potential jurors that the next couple of days will be some of the most important days in your client’s life. The jury needs to know there is a real human being sitting there at the defense table.

Before getting into the substance of our voir dire, how do we emotionally disarm the potential jurors in order for them to be completely open with us? After all, without doing this, how can we possibly expect to get the internet trolls out using strikes for cause, thereby allowing us to not squander our precious peremptory strikes? Perhaps during the judge’s or government lawyer’s voir dire, some of the jurors were open and honest about biases and are already locked down for cause. If so, great; but often there is a lot of head nodding and people going through the motions and not really being open about their feelings. People going along to get along aren’t going to fight for your client’s freedom. Most persons with biases haven’t said a word at this point. This is the moment when you have to use the rule for reciprocation to your advantage.

It’s a simple enough principle: Those who have given benefits to someone are entitled to benefits from them in return.5 Dr. Cialdini explains that “requesters who hope to commission the pre-suasive force of the rule for reciprocation have to do something that appears daring: they have to take a chance and give first without a formal guarantee of compensation.”6 The idea is that if we’re completely open and vulnerable with the panel, they will feel obligated to reciprocate and be open and honest with us. The psychological studies show that a person’s need to reciprocate is intensely strong. We should, therefore, let the panel know that before getting into their personal feelings about serious topics, we think it’s only fair that we be completely open and honest with them about us. In the spirit of total transparency, share with them the worst thing and best thing going on in your life right now.7

As an example, I tell the potential jurors about how we recently lost my father after a 2-year battle with AML leukemia as the worst thing, and how my wife and I finally got pregnant after several years and 5 IVF cycles as the best thing. This completely changes the atmosphere in the courtroom. You’ve humanized yourself, whereas the government’s lawyer probably got up there like a robot and didn’t say anything meaningful about themselves. In less than 90 seconds, at the very least, we have made the panel much more receptive to our subsequent narrative of the issues involved in the case. And at best, they’re now flat out rooting for us to win. This is the moment where we discard the role of underdog and move forward knowing that we’re now the favorites. We have become relatable.

Brainstorming what you will say in your introduction will take a lot of emotional energy and introspection. It forces you to connect with yourself and to find your unique voice, which is so hard to do in the modern, distracted world we live in today. In order to persuade a jury of the righteousness of our cause, we must find our true, authentic voice. This will make us a relatable human being instead of a paid mouthpiece or a slick lawyer. Get in touch with the real you and be vulnerable enough to show the jury the real you. As a caveat, this all has to come from an authentic place; otherwise, the jurors will smell it a mile away and sense an attempt at manipulation.

Once you get jurors openly discussing their feelings about the important issues, and sharing personal life experiences, make sure to connect on a personal level with the potential juror that just opened up to you. For example, if someone shares that they lost their son or daughter in a drunk driving accident and they can’t be fair, take a few moments to acknowledge their strength and courage in sharing, and to feel their pain. Don’t just quickly move on from them because you’ve locked them down for cause. Be a human being rather than a calculating lawyer. In this manner, hopefully, we’ve stricken all of the jurors that could not possibly consider the disconnect defense, and are now left with peremptory challenges that we can use to further solidify our final jury.

I hate to admit it, but I was resistant to adopting the use of PowerPoint in trials. I feared that it could interfere with connecting with the panel. Now I couldn’t imagine not using it. As we all know, everyone is attached to their phones and tablets. We live in a world where people are literally addicted to screen time. Let’s give potential jurors what they want: screen time while they’re in court! I notice most prosecutors using slides with lots of text on them. That’s because they’re using their PowerPoints as a crutch. Potential jurors aren’t interested in reading legal concepts. Instead, our goal with PowerPoint should be to use mostly cartoons, charts, and pictures to help them understand and reinforce key concepts. The few slides that do have text should consist of no more than three scaled questions, touching on sensitive topics in the case that concern you. Everything else should be mostly pictures accompanied by short phrases. The three questions should all have a consistent grading—i.e., favorable answers would be A or B and problematic or even strike-for-cause-type answers would be C or D. This way, when you’re deciding on how to exercise your peremptory strikes, all other things being equal between potential jurors, you have something objective on which to base your decision.

Heading into my .161 blood draw/T-bone accident trial, I was obviously concerned about the prospect of a juror voting guilty automatically if the evidence showed my client drank some amount of alcohol, then drove, and was subsequently involved in an accident. I recommend asking the entire panel to raise their hands if they’ve ever been involved in a car accident. You should get 95% of their hands up. Then follow up with how many have been involved in an accident where alcohol was not in any way involved. You’ll probably still have 95% of the panel with their hands up. It’s an easy way to point out that being involved in an accident doesn’t necessarily mean someone is intoxicated. (You can reinforce this concept when you cross-examine the officer. He will readily admit that alcohol is NOT a contributing factor in most accident scenes.) You can follow up with several jurors regarding what caused the accidents they were involved in. After this “pre-suasive” discussion, you can then present a couple of slides that ask how the potential jurors feel about the following statements:

I think you are automatically guilty of DWI if you drink ANY amount of alcohol and then get behind the wheel of a vehicle.

A) Strongly disagree
B) Disagree
C) Agree
D) Strongly Agree

I think you are automatically guilty of DWI if you drink ANY amount of alcohol and then get behind the wheel of a vehicle and cause an accident.

A) Strongly disagree
B) Disagree
C) Agree
D) Strongly Agree

If the prosecutors object, argue it’s not an improper commitment question, but rather a question to test the jurors’ understanding of the presumption of innocence. Obviously, at the end if you’re struggling with whom to strike, you want to err on the side of the As and Bs being on your jury. They’ve demonstrated by their responses that they are much more likely to be receptive to the disconnect defense. Of course, you also want to look for innocent explanations for how this accident happened—i.e., awkward intersection layout, texting, GPS, sleep deprivation, distracting passengers, etc.

Remind jurors that our client’s innocence is the only presumption in any criminal case. In other words, there can be no presumption that a breath or blood test is always reliable, valid, and accurate, or that the result necessarily corresponds to John Doe (switched vial theory in a blood case). Further, it’s not up to us to prove that a result is inaccurate and/or falsely attributed to our client. Rather, the Government has the burden to prove beyond a reasonable doubt that the result is accurate and is, in fact, indicative of our client’s blood and not someone else’s. In other words, at the end of the case, a juror should never be telling defense counsel, “You didn’t prove that the result was inaccurate.”

In a disconnect defense case, everything comes down to whether the jury believes the government’s “science”—i.e., the BAC result. Therefore, the credibility of the government’s expert witness will be a huge factor that goes into the jury’s decision-making process. Because of this, I recommend using three different PowerPoint slides to prime the jury to closely scrutinize what an expert testifies to and not just take what they say at face value simply because they’re an expert. Try to come up with something in the news or pop culture than can be analogized to the breath or blood expert in order to reinforce the idea that just because an expert says something does not necessarily make it so. We shouldn’t just ignore our common sense and let someone else think for us because of their credentials. After all, expert witnesses are there to help the trier of fact understand the evidence or determine a fact in issue,8 not completely replace the jury as the factfinders. The jurors must be empowered by reminding them they are the sole judges of the facts proved.

An example that proved effective for me was putting up an image of the gigantic plume of chemicals covering the greater Houston area following the ITC chemical plant fire in Deer Park with the short caption “ITC’s Expert: Air Quality Poses No Danger.” If you live in Deer Park and have been training for a marathon, are you going to listen to that expert and go for a six-mile run in those conditions, or are you going to question the narrative and the expert’s motivations and biases? You’d want proof. A lot of people have been watching “Chernobyl” on HBO. Many of the responses to that disaster of the Soviet Union’s government experts would be great fodder for this type of example. By focusing attention on experts early and often—i.e., what Dr. Cialdini calls the frontloading of attention—we’re creating an environment where jurors will be empowered to closely scrutinize the state’s star witnesses later during the trial rather than blindly accepting everything they say as truth.

Regarding the constitutional principles that apply in all criminal cases, including the various burdens of proof, I highly recommend Brent Mayr’s PowerPoint slides on the ring-the-bell analogy. The images on the slides are fantastic because they equate proof beyond a reasonable doubt with ringing a bell at a carnival, a near-impossible feat. Once again, we’re giving potential jurors a visual aid that will help them better learn these concepts.

Also, within the PowerPoint, you can change the text as needed to fit your case theory. For example, in my case with the switched-vial theory, under the column for beyond a reasonable doubt, I inserted “I have no reasonable doubt in my mind that the test was valid and accurate, and that it’s Mr. Doe’s blood.” By doing so, I’ve already focused the panel’s attention on the idea that the reported blood result may not even correspond to my client’s blood.

Okay: I Agree There Is a Disconnect, But Why?

As trial lawyers, we must be a surrogate for the jury. Know that the above question will be in their minds as they sift through the evidence. At this summer’s Rusty Duncan seminar, Troy McKinney shared some tips on presenting a disconnect defense. He took something as simple as a picture of a Great Dane and a Chihuahua standing next to one another to create a big dichotomy. The slide has an arrow pointing to the Great Dane with the caption saying: “I have a government DNA test report that says this is a Chihuahua. Do you believe it?” It then says, “Do you have to know why the report is wrong to know that it must be wrong?” This example can be a very powerful way to present a disconnect defense, especially where there isn’t anything specific in the breath or blood discovery that you can use to discredit the result.

While this is a great default position when one has an exculpatory video performance (and still allows for a viable disconnect defense), in order to further increase our chances of securing an acquittal we should strive to give the jurors cold, hard facts that they can hang their hats on to give the reported BAC result no weight in their decision-making process.9 Otherwise, the government will argue the excellent video performance is due to tolerance rather than innocence.

In my experience, jurors place a lot of weight on issues surrounding breaks in the chain of custody of the blood sample. Just because case law says that breaks go to the weight of the evidence rather than its admissibility doesn’t mean we shouldn’t be making a huge deal of the issue on cross-examination. While the lab typically is extremely thorough in documenting chain of custody once received, the police department that handled the sample prior to it getting to the lab normally is not so thorough. By establishing that the lab’s analysis is only as good as the integrity of the sample they receive from the police agency, we can successfully undermine the result.

For example, if the sample was stored at the police department for a few days before being sent out, where exactly was it? Under what conditions was it stored? Was it refrigerated? If it was mailed to the lab, was in sent in a cooler? The blood analyst will readily admit that they have no knowledge or control over the quality of the sample they receive from law enforcement. Garbage in, garbage out.

Also look at the entire batch run to see if there are .000s or other BACs around .08 or under. In my .161 case, 7 of the 30 citizen samples tested reflected a BAC of .000, while 2 others were at or below .08. If you have a truly exculpatory video/disconnect case, arguing that your client’s sample was accidentally switched suddenly becomes much more plausible with this one document in evidence. In fact, you can argue it’s the only logical explanation for why there is such a huge disconnect between what we can see and hear on video versus the lab’s number.

Remember that we don’t have to prove human error happened. In fact, how could we ever prove it happened? The analyst will always testify that they’ve never accidentally switched vials. Rather, the government must prove beyond a reasonable doubt that this didn’t happen. Note that jurors don’t have to agree as to why they are choosing to not give weight to the reported BAC result. Some can say they don’t know why it’s wrong, they just know it must be wrong, given all the evidence of sobriety. Some can say they are unsure whether the sample the lab received was viable for analysis (chain of custody, short draws, bad venipuncture technique). Others can say the sample must have been accidentally switched—i.e., human error in the lab. Each juror can have different reasons for their reasonable doubt, so long as they each have at least a reasonable doubt that goes toward whether the government proved intoxication.

In closing argument, acknowledge that what you’re asking the jury to do is hard and it will require a lot of courage, but it’s the right thing to do. Imagine that all your jurors live next door to police officers, and after the trial they will eventually talk to them about the work they did in that courtroom. They must be empowered to have the guts and independence to stand up for the people. There should be no shame in them telling their cop neighbors that they had to find the client NOT GUILTY because the government’s evidence just didn’t add up. Show a slide of one of the disconnect pictures used in voir dire and add the caption “The government wants you to believe Mr. Doe’s BAC was a .18 at the time of driving, even though he had the normal use of his mental and physical faculties and didn’t smell like alcohol?”

Remind them that they, individually and collectively, are the exclusive judges of the facts proved and the weight to give the evidence, including the government’s purported BAC results. We don’t do trials by police officer or trials by expert witnesses for a reason. The accused is entitled to a trial by jury, because the jury is the accused citizen’s last line of defense. For the final slide, put up a picture of the statue of liberty, the constitution, or the American flag. When the State’s “science” is riddled with commonsense, reasonable doubt due to the overwhelming majority of the other evidence being consistent with sobriety, the law demands a verdict of NOT GUILTY, because we err on the side of freedom in America.


1. See Mark Thiessen’s articles on the Disconnect Defense, including

2. Thank you to Mark Bennett for recommending we all read Influence: The Psychology of Persuasion and Pre-Suasion: A Revolutionary Way to Influence and Persuade, both by Robert B. Cialdini, PhD.

3. In this case, the client did extremely well on SFSTs. His speech was not slurred, his eyes were not bloodshot, and no one on scene smelled alcohol on him.

4. Thanks to Jed Silverman for this tactic.

5. Pre-Suasion, page 153.

6. Id. at 154.

7. Thanks to Mark Thiessen for this introduction. See “Eleven Essential DWI Trial Tactics,” Voice for the Defense, May 2014.

8. Tex. Rules Evid. 702.

9. To this end, I recommend using an expert like Amanda Culbertson to review the discovery in order to help find issues that you can use to strengthen your disconnect defense.