Texas DWI Glossary: 55 Terms, Explained

Key Terms

The words that come up most on this page, in plain English.

Administrative License Revocation (ALR)

The civil process that suspends your driving license after a DWI arrest, entirely separate from the criminal case. It is triggered by refusing a breath or blood test, or by providing a specimen showing the prohibited concentration. You have 15 days from the notice of suspension to request a hearing, counting the day you received it as day one. Miss that deadline and the suspension takes effect automatically on the 40th day, with no hearing at all. ALR Hearings

Alcohol-Related Enforcement Contact

A time you actually lost your license, in Texas or any other state, because of a conviction for driving while intoxicated, a refusal to give a breath or blood specimen after that kind of arrest, or a test result at or above the limit. A prior arrest that never cost you your license is not a contact. One in the ten years before your arrest lengthens the suspension itself; one in the five years before it delays an occupational license. Texas License Suspension Periods

Blood Alcohol Concentration (BAC)

The amount of alcohol in a person’s blood, expressed in Texas as grams of alcohol per 100 milliliters of blood. The legal threshold is 0.08. A breath result is reported in different units, grams per 210 liters of breath, and the two are treated as equivalent under a fixed conversion assumption.

Blood Search Warrant

A warrant authorizing police to take a blood specimen, issued by a magistrate on a sworn affidavit establishing probable cause. Since 2013 police generally cannot take blood without one, because the natural dissipation of alcohol does not by itself create an emergency. Warrants are challengeable on several grounds, including whether an oath was actually administered.

Chain of Custody

The documented sequence of every person who handled a specimen, with the date and time of each transfer. Gaps matter: an unexplained interval between a blood draw and refrigeration is exactly the window in which a sample can ferment and generate its own alcohol.

Community Supervision

What Texas law calls probation. The judge suspends imposition of the sentence and releases you under conditions for a set term, typically measured in years rather than months. Violating a condition lets the State move to revoke, at which point the judge can impose up to the original sentence. DWI supervision cannot be terminated early. DWI Probation in Texas

Consensual Encounter

A conversation with an officer that you are free to walk away from. Because it is not a detention, it needs no reasonable suspicion, which is why the question of when an encounter became a stop matters so much: everything after that moment requires justification. Your Rights During a Texas DWI Stop

Deadly Weapon Finding

An affirmative finding that a motor vehicle was used or exhibited in a manner capable of causing death or serious bodily injury during a felony. It denies judge-ordered community supervision, delays parole until actual calendar time served without good conduct credit equals half the sentence or 30 years, whichever is less, and raises a state jail felony to third degree felony punishment under Penal Code §12.35(c). It does not apply to misdemeanors. Deadly Weapon Findings

Deferred Adjudication

A disposition placing a defendant on community supervision without a finding of guilt, available for DWI offenses committed on or after September 1, 2019, the first time since 1983. It is deferred in name only in one respect: it can still be used for enhancement purposes. It is unavailable to anyone who held a commercial license at the time of the offense, anyone with an alcohol concentration of 0.15 or higher, and anyone with a prior DWI-related conviction.

DIC-24

The statutory written warning an officer reads to you before requesting a breath or blood specimen. It sets out the consequences of refusing and of failing the test. What you were told, and whether it was accurate, goes directly to whether any consent you gave was voluntary.

DIC-25

The Notice of Suspension. An officer hands it to you at the arrest if you refused a specimen or failed a breath test, and it is mailed to you later where you gave a blood specimen voluntarily, because at the roadside the result does not exist yet. Either way, receiving it starts the deadline to request an ALR hearing: 15 days from a notice handed to you, 20 from a mailed one. Since September 2023 it is a notice only and no longer works as a temporary driving permit, and officers no longer take your plastic license. ALR Hearings

Disposition Meeting

The setting where your lawyer and the prosecutor discuss how the case might resolve, before any trial date. Most Texas DWI cases are decided in these conversations rather than in front of a jury, which is why the evidence your lawyer has gathered by then shapes the outcome. Your First DWI Court Date

Drug Recognition Expert (DRE)

A police officer, not a physician, trained over roughly 112 hours to conduct a 12-step post-arrest evaluation and name the category of drug causing impairment. The opinion is rendered at step 11; blood or urine is collected at step 12, and the result is used to support the conclusion already written. A Texas study put the median accuracy at 53.2 percent.

Employer-Owned Vehicle Exception

The rule letting a driver restricted to an interlock-equipped vehicle drive an employer’s vehicle without a device. All five conditions have to be true: the driving is part of the job, the employer owns the vehicle, the driver does not own or control that employer, the employer has been told about the restriction, and proof of that notice stays in the vehicle. It exists for employees driving a fleet vehicle, not for owners driving a company truck. The Interlock Occupational License

Expunction

The removal of a DWI arrest from your criminal history under Article 55 of the Code of Criminal Procedure. It is generally available where you were found not guilty, or the case was declined or dismissed, and also after a pardon or an acquittal even following a conviction. An expunction order becomes final 30 days after signing, at which point you may deny both the arrest and the existence of the order. The single exception: if questioned under oath in a criminal proceeding about it, you must answer only that the matter has been expunged.

Gas Chromatography

The forensic method used to measure alcohol in blood. A separation science: a heated sample releases volatile compounds into the space above the liquid, that gas is pushed through a long column where compounds separate by how fast they travel, and each is detected as it exits. The result is indirect, calculated from the ratio between your ethanol peak and a known internal standard, which means errors in sample preparation shift the number either way.

Hard Suspension

The everyday name for the delay before an occupational license order can take effect, applied when you have a qualifying prior alcohol or drug suspension. It runs 90 days, 180 days, or a full year depending on what the prior was, and it is measured from the date your suspension started rather than the date you file. Installing an ignition interlock on every vehicle you own or drive removes it entirely. Occupational License Eligibility

Horizontal Gaze Nystagmus (HGN)

The eye test. The officer moves a stimulus horizontally and looks for six clues across both eyes, three per eye. It is scientific evidence, so it is admissible only if the State proves the technique was properly applied on the occasion in question. The protocol has required minimum timings, which makes that checkable on video. An officer may not correlate your performance to a specific alcohol concentration.

Ignition Interlock Device (IID)

A breath testing device wired to a vehicle’s ignition, preventing it starting unless a clean sample is given, and requiring further samples while driving. It appears as a bond condition, a probation condition, and as the basis for one form of occupational license. A magistrate may choose not to require one where it would not be in the best interest of justice.

Implied Consent

The rule that a person arrested for DWI after operating a motor vehicle in a public place is deemed to have consented to giving a breath or blood specimen. You may withdraw that consent and refuse, which triggers a license suspension, but refusing does not prevent police obtaining a warrant.

Interlock Occupational License

The occupational license granted on proof of insurance and an ignition interlock on every vehicle you own or drive, created in September 2015 and also called a DLD ODL. No hearing is required, no essential need has to be shown, and the court cannot limit when, where, or why you drive. It is the only option where a conviction caused the suspension, and it erases the waiting periods that otherwise apply to a driver with a prior. The Interlock Occupational License

Intoxilyzer 9000

The evidential breath testing instrument used in Texas, replacing the Intoxilyzer 5000EN. It measures how much infrared light alcohol absorbs inside a sample chamber. It can record the observation period, whether you were seen to burp, and its own measurement uncertainty, and it can print a histogram showing the shape of your breath. Texas prints none of it.

Involuntary Intoxication

Becoming intoxicated without intending to, for example through a spiked drink or a medication error. This is not a defense to DWI in Texas, because the offense requires no culpable mental state, so the State never has to prove you intended anything. The related defense that does exist is the involuntary act, or automatism, defense.

Loss of Normal Use

One of the two ways Texas defines intoxication: not having the normal use of mental or physical faculties. “Normal use” is not defined by statute, and a trial court should not define it in a jury instruction. The question that follows, and it is a real one, is whose normal matters, since the officer meeting you for the first time at the roadside has no baseline for you.

Magistration

The first appearance before a magistrate after arrest, where you are informed of the charge and your rights, bail is set, and conditions of bond are imposed. Interlock and alcohol monitoring conditions are frequently set here, which is why conditions are far easier to shape at this stage than to modify afterwards.

Mata v. State

The 2001 Court of Criminal Appeals decision governing the admissibility of retrograde extrapolation. It holds the technique can be reliable, but only where the expert understands the difficulties and subtleties involved, applies the science clearly and consistently, and knows enough about the individual. Courts also weigh the time between the offense and the test and the number of tests given. Texas convictions have been reversed where these factors were not established.

Michael Morton Act

The Texas discovery statute, effective January 1, 2014, designed to prevent wrongful convictions by requiring prosecutors to be more transparent about potentially exculpatory evidence. Before it, disclosure practices varied county by county, from open files to reading portions aloud. Now the State must open its file on receipt of a request from the defense, with no need to apply to the court and show good cause.

Miranda Warning

The warning required before custodial interrogation, covering the right to remain silent and the right to counsel. It is narrower than people expect in a DWI case: much of what happens at the roadside is not treated as custodial interrogation, so the absence of a warning during a traffic stop is often not the issue people assume it is.

Motion to Revoke

The State’s application to revoke community supervision for an alleged violation. It can be filed at any time within the probationary period, including in the final month.

Motion to Suppress

A pretrial motion asking the court to exclude evidence obtained unlawfully, heard outside the presence of the jury. At the hearing the defendant carries the initial burden of producing evidence of the violation; only then does the State have to justify what it did. At trial that reverses, and the State must satisfy every evidentiary predicate.

Necessity Defense

A justification available where a person reasonably believed conduct was necessary to avoid imminent harm, and the urgency of avoiding that harm clearly outweighed the harm the law prevents. It applies to driving while intoxicated, but Texas courts distinguish a life-threatening event from a need to get home, and the justification ends when the emergency does.

NHTSA

The National Highway Traffic Safety Administration, the federal agency that developed and publishes the standardized field sobriety testing program and its training manuals. The manuals have been revised repeatedly, and which edition an officer was trained under can matter, because warnings present in earlier editions were removed from later ones.

No-Refusal Weekend

A period, usually a holiday weekend, during which prosecutors and magistrates are on standby so that blood search warrants can be obtained quickly when a driver refuses testing. It does not change the law. Refusing remains lawful; it simply means a warrant is likely to follow faster.

Nystagmus

Involuntary jerking of the eyes. It is a category, not a single condition. Types include vestibular nystagmus (rotational, post-rotational, caloric, positional) and neural nystagmus (optokinetic, physiological, gaze), and pathological causes include brain tumors, brain damage, and inner ear disease. Officers are trained to screen for medical causes before the eye test.

Occupational Driver’s License (ODL)

A limited-purpose license permitting driving for work, school, and essential household duties during a suspension. It can only replace a suspended Class C license, and a court may not grant one to a person who drives on a commercial license.

Operating a Motor Vehicle

An element of the offense, and there is no statutory definition. Courts ask whether the totality of the circumstances shows you took action to affect the functioning of the vehicle in a way that would enable its use. Driving involves operating, but operating does not necessarily involve driving, and no movement is required. People have been found to be operating with the car against a curb, and with the engine off.

Order of Nondisclosure

An order sealing criminal records from public disclosure, as distinct from an expunction, which destroys them. Sealed records remain accessible to certain agencies. Nondisclosure is the route generally available where a case ended in a way that does not qualify for expunction, such as a reduction to a different offense.

Padilla v. Kentucky

The 2010 United States Supreme Court decision holding that defense counsel must advise a non-citizen client about the immigration consequences of a guilty plea, and that failing to do so can amount to ineffective assistance of counsel. What those consequences are in any given case is a federal question requiring immigration counsel.

Partition Ratio

The conversion factor used to turn a breath measurement into a blood alcohol figure. Texas uses 2100 to 1, set by the National Safety Council in 1952. Real human ratios have been measured from about 1555 to 1 up to 3005 to 1, and an individual’s own ratio changes over an evening. A ratio below 2100 to 1 produces a result higher than the person’s true concentration, and the ratio is at its lowest during absorption.

Personal Bond

Release on your own written promise to appear, without posting a cash or surety bond. Certain conditions attach specifically to defendants released on personal bond, including drug and alcohol testing requirements.

Portable Breath Test (PBT)

The handheld device sometimes offered at the roadside. It is not the evidential test, and in Texas its result is admissible only for the limited purpose of showing the presence of alcohol, not to prove a concentration. It should not be confused with the station instrument.

Pretrial Diversion

A county program that suspends prosecution while you complete a set of requirements, ending in a dismissal if you finish. Availability is set county by county rather than by statute, so the same case can be eligible in one county and not the next. Texas DWI Pretrial Diversion

Probable Cause

The standard required to arrest, and to obtain a search warrant. It is a higher standard than reasonable suspicion, requiring facts sufficient to warrant a reasonable belief that an offense has been committed. A warrant affidavit must set out facts establishing it, not conclusions.

Public Place

An element of the offense: the operation must have occurred in a public place. Texas courts have found some locations qualify and others do not, which makes private driveways, gated communities, private lots, and restricted-access land worth examining. It is an element the State must prove.

Reasonable Suspicion

The standard justifying a brief investigative detention: specific, articulable facts supporting a suspicion that a person has committed or is about to commit an offense. Lower than probable cause, but not satisfied by a conclusion. Testimony that a driver was traveling at “a high rate of speed,” with no measurement and no reference to the limit, has been held insufficient.

Reinstatement Fee

The fee owed to DPS before a suspended license is restored, currently $125 for an ALR suspension. The suspension period running out does not lift the suspension on its own, and nobody bills you for the fee, so drivers routinely discover months later at a traffic stop that the license they thought was back never came back. No fee is owed where an administrative law judge denied the suspension. Getting Your Texas License Back

Retrograde Extrapolation

Calculating what your alcohol concentration was at the time of driving from a sample taken later, typically 30 minutes to three hours afterwards. It depends on assumptions about absorption and elimination that vary enormously. Absorption times have been measured from 14 minutes to 138 minutes, and it is not possible to determine which phase a person was in from two consecutive measurements.

SCRAM (Continuous Alcohol Monitoring)

An ankle-worn device that samples perspiration to detect alcohol consumption continuously, rather than at the point of driving. It appears as a bond condition and a probation condition, and unlike an interlock it monitors the person rather than the vehicle.

Serious Bodily Injury

The injury threshold converting a DWI into intoxication assault, a third degree felony. It means injury that creates a substantial risk of death, or causes serious permanent disfigurement, or causes protracted loss or impairment of the function of any bodily member or organ. Texas courts have held that not every injury, and not even every serious injury, meets it.

State Office of Administrative Hearings (SOAH)

The independent state agency whose administrative law judges hear ALR cases. The hearing is civil rather than criminal, and it is usually the first opportunity to put the arresting officer under oath, months before trial. Recordings of these hearings are kept only 60 days.

SR-22

An endorsement your insurer attaches to a real auto policy and files with the state to confirm you carry the required liability coverage. It is not a standalone certificate and cannot be bought on its own. It carries an effective date and no expiry, staying in force until the insurer files an SR-26, and Texas expects it to be maintained for two years from the date of conviction. SR-22 Insurance

SR-26

The cancellation half of the SR-22. When the policy carrying an SR-22 endorsement cancels for any reason, including switching companies, the insurer must file an SR-26 with DPS. If an SR-22 is still required at that moment, DPS can begin suspending again without further notice to you, which is how a lapse becomes an invalid license nobody mentioned. SR-22 Insurance in Texas

Standardized Field Sobriety Tests (SFST)

The three-test battery: horizontal gaze nystagmus, the walk and turn, and the one leg stand. They emerged from research that began with sixteen candidate tests in 1977. Everything else an officer asks you to do at the roadside, including reciting the alphabet, counting backwards, the finger count, and the Romberg, is non-standardized, unvalidated, and has no scoring system.

Super Fine

An additional fine under Transportation Code §709.001, charged on top of the ordinary DWI fine and separate from court costs. It is $3,000 for a first conviction within a 36-month period, $4,500 for a second or subsequent conviction in that period, and $6,000 where the alcohol concentration was 0.15 or higher. It reaches people finally convicted, which Texas prosecutors have generally read to exclude probated sentences. Texas DWI Fines & Court Costs

Vehicle Forfeiture

The State taking permanent possession of the vehicle used in an offense. In Texas DWI cases the threshold is high: a felony-level intoxication offense and three prior convictions under the same chapter, so a first, second or typical third offense is not exposed. Getting Your Car Back