Alcohol, Drugs and Crashes: DWI Law, Zero Tolerance, Implied Consent, and What to Do After a Crash
Written for aiforu2 as the source for a practice-test bank and the on-device tutor for the Texas Class C knowledge exam. The facts follow the official handbook; the wording is ours.
Source: Texas Driver Handbook (DL-7), Texas Department of Public Safety, rev. January 2026, chapter 10 "Alcohol and Drug Impact on the Driving Ability" (pp. 55–58) and chapter 11 "Motor Vehicle Crashes" (pp. 59–60).
How alcohol and drugs affect driving
Any drug, prescription, over-the-counter or illegal, can affect the mental and physical skills driving needs, and the same drug affects different people differently depending on body weight, emotional state, dose and timing. The first things alcohol or drugs take are judgment and sight: reactions to sound slow, the ability to judge another vehicle's speed goes, and reason can all but disappear. Mixing drugs is worse, especially with alcohol, which both escalates and masks the effects of other drugs; check with a doctor or pharmacist before combining anything, above all tranquilizers or sedatives.
- Marijuana: even social doses impair concentration, judgment and the sensory and perceptual skills driving needs.
- Stimulants: heavy amphetamine use keeps a driver awake but less coordinated, edgy and more crash-prone; social amounts of cocaine cause lapses in attention. Caffeine can help a drowsy driver stay alert but cannot sober a drunk one.
- Tranquilizers and sedative-hypnotics (including barbiturates) are powerful depressants; a sedated driver is not a good driver.
- Over-the-counter drugs: antihistamines, cold remedies and anything that relaxes or induces sleep can cause drowsiness; read the label.
- Alcohol is a depressant that affects coordination, judgment, perception and emotional state, and increases the effect of tranquilizers and barbiturates.
Alcohol is the number one killer. In 2018, 940 people died in Texas crashes involving a driver under the influence of alcohol, about 26 percent of all crash deaths; nearly 7 percent of fatal crashes involved a drinking driver under 21, and nationally about a quarter of teen drivers in fatal crashes had been drinking. A person 21 or older is legally intoxicated at a BAC of 0.08 or more, or at any level that causes loss of the normal use of mental or physical faculties. Fines can reach $10,000 before bail, lawyers and court costs.
Open container: having an open container of alcohol in the passenger area of a vehicle on a public highway is illegal whether the vehicle is moving, stopped or parked: a fine of up to $500.
Myths: cold showers, black coffee and exercise do not sober anyone. Only time does, roughly one hour per drink, depending on body weight, number of drinks and food. If a person has been drinking, someone who has not should drive. A drink is a 12-ounce beer, a mixed drink with 1.5 ounces of liquor, or a 5-ounce glass of wine; all hold about the same alcohol. The handbook's BAC chart shows, for example, that at 160 pounds two drinks give about .05 and four drinks about .09; "influenced" begins at one drink, "impaired" at around three, and legal intoxication at .08. Insurance companies may discount liability premiums for drivers who complete a drug and alcohol awareness course.
Minors: zero tolerance
A minor is anyone under 21. A minor may not buy, try to buy, consume or possess alcohol, and a minor driving in a public place, or operating a watercraft, with any detectable amount of alcohol commits Driving Under the Influence of Alcohol by a Minor, even below 0.08.
Non-driving alcohol offenses (buying, attempting to buy, claiming to be 21, showing a false document, consuming, possessing): 1st, Class C misdemeanor, up to $500, 8 to 12 hours community service, mandatory alcohol awareness course (a parent may have to attend if the minor is under 18), license suspended 30 days; 2nd, up to $500, 20 to 40 hours, suspended 60 days; 3rd under 17, up to $500, 20 to 40 hours, 60 days or juvenile court; 3rd aged 17 to 20, Class B misdemeanor, $250 to $2,000, 40 to 60 hours, up to 180 days in jail, suspended 180 days, and no deferred disposition. Supplying alcohol to a minor: up to $4,000 and/or up to a year in jail. A minor convicted of a moving violation while suspended for one of these offenses faces DWLI penalties.
Implied consent (minors): by driving, a minor consents to breath or blood testing when arrested for intoxicated driving or boating, or when an officer notes any detectable alcohol. Refusing the specimen: suspended 180 days for a first refusal, 2 years after that. A specimen showing alcohol below 0.08: suspended 60 days (1st), 120 days (2nd), 180 days (3rd and later). The minor may request a hearing.
DUI by a minor (any detectable alcohol): 1st, Class C, up to $500, 20 to 40 hours community service, mandatory alcohol course; 2nd, up to $500, 40 to 60 hours; 3rd under 17, the same or juvenile court; 3rd aged 17 to 20, Class B misdemeanor, $500 to $2,000 and/or up to 180 days in jail, 40 to 60 hours, suspension for one year, or 90 days with an ignition interlock ordered by the judge.
DWI by a minor (0.08 or more): 1st, Class B misdemeanor, up to $2,000, 72 hours to 180 days in jail, suspension 365 days (or 90 days with an interlock); the court may probate the jail term and waive the suspension on a first offense only, and an open container raises the minimum jail to six days. 2nd, Class A, up to $4,000, 30 days to a year, suspension 180 days to 18 months. 3rd and later, third-degree felony, up to $10,000, 2 to 10 years in prison, suspension 180 days to 18 months.
Adults: implied consent and DWI penalties
An adult likewise consents to breath or blood testing when arrested for intoxicated driving or boating (and, up to age 21, for any detectable alcohol). Refusing the specimen suspends the license for 180 days, up to 730 days for later refusals. A specimen of 0.08 or more suspends it for 90 days, up to 365 days for later offenses.
| Offense | Fine | Confinement | License suspension |
|---|---|---|---|
| 1st DWI | up to $2,000 | 72 hours to 180 days in jail | 90 to 365 days |
| 2nd DWI | up to $4,000 | 30 days to 1 year in jail | 180 days to 2 years |
| 3rd and later | up to $10,000 | 2 to 10 years in prison | 180 days to 2 years |
| DWI with a passenger under 15 | up to $10,000 | 180 days to 2 years in state jail | 90 days to 2 years |
| Intoxication assault | up to $10,000 | 2 to 10 years in prison | 90 days to 2 years |
| Intoxication manslaughter | up to $10,000 | 2 to 20 years in prison | 180 days to 2 years |
Crashes
Most Texas crashes come from speeding, failure to yield or stop, and driving under the influence. After a crash, exchange names, addresses, phone numbers, VINs, plate numbers, license and insurance details with every driver, copying the insurer and policy number exactly from the insurance card; the Texas Department of Insurance at (800) 252-3439 can supply an insurer's address. Note the location and any witnesses' contact information.
Call law enforcement as soon as possible when there is an injury or death, when the vehicles cannot be moved off the road, when a driver leaves the scene, or when you suspect a driver is intoxicated. A crash that no officer investigates, with no injury or death and damage under $1,000, still requires a written report to TxDOT on its form within 10 days.
Injury or death
Stop immediately at the scene, or as close as possible without blocking traffic more than necessary, and stay (or return at once) until you have: given your name, address, vehicle registration number and liability insurer to anyone injured and to the driver, occupants or attendant of any vehicle involved; shown your license on request; and given any injured person reasonable assistance, including taking or arranging transport to a doctor or hospital when treatment is clearly needed or the person asks. Failing to stop: a crash causing death is a second-degree felony, up to $10,000 and 2 to 20 years; serious bodily injury, a third-degree felony, up to $10,000 and 2 to 10 years; injury, up to 5 years in prison or a year in county jail and/or up to $5,000.
Damage only
If only a vehicle driven or attended by someone is damaged, stop at the scene or as close as possible. On a main lane, ramp, shoulder, median or adjacent area, if every vehicle can be driven normally and safely, drivers must move them to a designated crash investigation site, the frontage road, the nearest suitable cross street or another suitable place. Then give your name, address, registration number and insurer, and show your license on request. Leaving without doing so: damage under $200, Class C misdemeanor, up to $500; $200 or more, Class B, up to $2,000 and/or up to 180 days.
Unattended vehicle: stop and either find the owner or driver and give your name and address, or leave a written notice securely attached in a visible place with your name, address and what happened. Same penalties.
Fixture, landscaping or structure beside the road: take reasonable steps to find the owner or person in charge, give your name, address and registration number, show your license on request, and file the TxDOT report within 10 days if no officer investigates and damage to any one person's property is under $1,000. Same penalties.
Hit-and-run: report it to law enforcement; uninsured motorist coverage pays for damage from a hit-and-run reported to the police.
Aiding the injured
When calling for help, state the location clearly. Do not assume people are unhurt because they say so; send for skilled help quickly, since unskilled handling can do harm. Do not move a victim unless absolutely necessary, and then keep the position they were found in. Stop serious bleeding with clean, thick cloth pads and pressure. Keep victims comfortable: shade and cooling in heat, blankets or coats in cold.
Practise this with Texas Driver License questions
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