Colorado DUI Laws

The per se limit is 0.08: driving with a BAC of 0.08 or more at the time of driving or within two hours after is DUI per se, a complete offense by itself (§ 42-4-1301(2)(a)). Below 0.08 you can still be charged. A BAC in excess of 0.05 but less than 0.08 permits an inference of the lesser offense of driving while ability impaired (DWAI), and a BAC of 0.05 or less is presumed neither under the influence nor impaired — a rebuttable presumption, not an absolute safe harbor, because other evidence of impairment remains admissible (§ 42-4-1301(6)(a)-(b)). DUI itself can also be proven without any number, on evidence of substantial incapacity to drive safely. Commercial drivers face a 0.04 administrative threshold in a commercial vehicle, and drivers under 21 face the separate 0.02-to-0.05 UDD offense.

They are two distinct criminal offenses in the same statute, separated by degree of impairment. DUI means the driver was "substantially incapable" of safe operation (or at 0.08+ BAC, DUI per se); DWAI means alcohol or drugs affected the driver "to the slightest degree" — a lower bar, typically associated with the over-0.05-under-0.08 band (§ 42-4-1301(1)(f)-(g), (6)(a)). A first DUI carries 5 days to 1 year in jail, $600-$1,000, and 12 points; a first DWAI is lighter — 2 to 180 days, $200-$500, and 8 points — and triggers no conviction-based license revocation by itself (§ 42-4-1307(3)-(4); § 42-2-127(5)(b)). But DWAI is NOT a free pass: it is a criminal conviction that counts as a prior on the same ladder as DUI, second and third offenses of either kind share one penalty grid, and a fourth offense of either kind is a class 4 felony.

A first DUI or DUI per se conviction is a misdemeanor carrying 5 days to 1 year in county jail, a $600 to $1,000 fine, and 48 to 96 hours of useful public service that the court cannot suspend (§ 42-4-1307(3)(a)). The five-day jail minimum is mandatory but the court may suspend it if you complete the alcohol evaluation and the level I or II program it indicates — and if your BAC was 0.20 or more, the minimum is ten days instead (§ 42-4-1307(3)(b)). The court may add up to two years of probation. Mandatory surcharges (persistent-drunk-driver $100-$500, brain-injury $25, rural $1-$10, data-analysis $2, plus costs) ride on top of the fine. The conviction carries 12 points, and your license is revoked for 9 months — with early reinstatement on an interlock-restricted license available to a first offender 21 or older at any time (§ 42-2-125(1)(b.5); § 42-2-126(3)(a)(I)(A); § 42-2-132.5(4)(a)(II)).

A first DWAI is a misdemeanor carrying 2 to 180 days in jail (the two-day minimum is suspendable if you complete the indicated alcohol program), a $200 to $500 fine plus the mandatory surcharges, 24 to 48 hours of useful public service, and 8 license points (§ 42-4-1307(4); § 42-2-127(5)(b)(III)). A first DWAI conviction by itself triggers no license revocation — though an excess-BAC test or a refusal from the same stop still triggers the administrative revocation, and a BAC of 0.20 or more raises the jail minimum to ten days. The critical point: a DWAI counts as a prior exactly like a DUI. A second offense of either kind lands on the shared 10-day-minimum grid, a third on the 60-day grid, and a fourth offense of either kind is a class 4 felony (§ 42-4-1307(5)-(6); § 42-4-1301(1)(b)).

With one prior — DUI, DUI per se, DWAI, vehicular homicide, vehicular assault, or a listed alcohol-related driving-under-restraint conviction, counted over your lifetime with no time window and including out-of-state convictions — a second offense carries 10 consecutive days to 1 year in jail, $600 to $1,500 plus surcharges, 48 to 120 hours of public service, and mandatory probation of at least two years with a suspended one-year jail sentence held over you (§ 42-4-1307(5), (7), (9)). The ten-day minimum cannot be suspended through a treatment program, and no good-time reductions apply during it; if the prior was within five years, work-release-style alternatives during the minimum are limited to keeping an existing job or school placement or attending a level II program (§ 42-4-1307(5)(b)). Your license is revoked — one year on the administrative counter for a second excess-BAC test — and after reinstatement you must drive on an ignition interlock for two to five years (§ 42-2-126(3)(a)(I)(B); § 42-2-132.5(1)(b), (3)).

The FOURTH offense is the felony, not the third. A third offense (two priors) is still a misdemeanor — but a serious one: 60 consecutive days to 1 year in jail with no program suspension and no good-time during the minimum, $600 to $1,500 plus surcharges, 48 to 120 hours of public service, at least two years of probation with a suspended one-year jail term, and at least 90 days of continuous alcohol monitoring (§ 42-4-1307(6), (7)(b)). It also brings an indefinite license revocation with a two-year minimum (§ 42-2-125(1)(i)). A FOURTH or subsequent offense — after three or more prior convictions for DUI, DUI per se, DWAI, vehicular homicide, or vehicular assault, from separate criminal episodes, counted for life — is a CLASS 4 FELONY: 2 to 6 years in state prison (up to 12 with extraordinary aggravation) plus 3 years of mandatory parole and a $2,000 to $500,000 fine, or a probation sentence that still requires 90 to 180 days of jail (or 120 days to 2 years of work-release jail) and 90 days of continuous alcohol monitoring (§ 42-4-1301(1)(a); § 18-1.3-401; § 42-4-1307(6.5)).

For the criminal penalty ladder, forever. Colorado has no lookback window: a prior conviction for DUI, DUI per se, DWAI, vehicular homicide, vehicular assault, or a listed alcohol-related driving-under-restraint offense counts no matter how old it is, and equivalent convictions from other states, federal courts, and U.S. territories count too (§ 42-4-1301(1)(j); § 42-4-1307(9)). The year-figures that do appear in the law serve narrower purposes: a prior within FIVE years limits alternative sentencing during the second-offense jail minimum (§ 42-4-1307(5)(b)); a SEVEN-year spacing rule governs residential-treatment probation on a third offense (§ 42-4-1307(6)(c)); and the habitual-traffic-offender statute uses its own 7-year window (§ 42-2-202), with a 5-year revocation (§ 42-2-205(1)(a)). The administrative license counter is likewise lifetime — a third excess-BAC revocation applies "regardless of when the prior violations occurred" (§ 42-2-126(3)(a)(I)(C)).

Two independent tracks run at once, and same-incident actions overlap rather than stack. The ADMINISTRATIVE track starts at the arrest: a BAC test of 0.08 or more brings a revocation of 9 months for a first violation, 1 year for a second, and 2 years for a third or subsequent (counted over your lifetime); a refusal brings 1, 2, then 3 years (§ 42-2-126(3)). The CONVICTION track adds a 9-month revocation for a first DUI conviction at 21 or older (skipped if the administrative revocation from the same incident already issued), 12 points for DUI or 8 for DWAI, and — after three convictions — an indefinite revocation with a 2-year minimum (§ 42-2-125(1)(b.5), (1)(i); § 42-2-127(5)(b)). When both tracks act on the same incident the periods run concurrently, capped at the longer one (§ 42-2-126(4)(a)(II)). Early reinstatement with an interlock-restricted license is broadly available — immediately for a first offender 21 or older, and for most revocations of a year or more (§ 42-2-132.5(4)).

Usually, if you want to drive again before your revocation fully runs out — and always in the higher-risk cases. The interlock-restricted license is Colorado’s early-reinstatement mechanism: a first offender 21 or older may apply at any time during the 9-month revocation and may drop the device after four consecutive violation-free monthly reports (§ 42-2-132.5(4)(a)(II)). The interlock becomes MANDATORY — at least two years of it — for any "persistent drunk driver": a BAC of 0.15 or more, a test refusal, two or more alcohol-related convictions or revocations, or driving after an alcohol-related restraint (§ 42-1-102(68.5); § 42-2-132.5(3)). Multiple DUI/DWAI convictions bring two to five years of interlock after the revocation ends (§ 42-2-132.5(1)(b)), and courts may order an interlock as a bond or probation condition (§ 42-4-1307(8)). Heads up: effective June 1, 2027, HB26-1242 (signed May 28, 2026) will require ALL first-time offenders to hold an interlock-restricted license for nine consecutive months after reinstatement — under current law that nine-month rule is not yet in force.

Refusal is not a separate crime — no jail attaches to the refusal itself — but it costs more than failing the test. The Department of Revenue revokes your license for 1 year on a first refusal, 2 years on a second, and 3 years on a third (§ 42-2-126(3)(c)), versus 9 months for a first excess-BAC result. A refusal automatically makes you a "persistent drunk driver," which means a mandatory level II alcohol program and at least two years on an interlock-restricted license to get back on the road (§ 42-1-102(68.5)(a)(IV); § 42-2-132.5(3)); early reinstatement with the interlock is available after two months of a refusal revocation (a wait a signed 2026 law eliminates effective June 1, 2027). The refusal is also admissible against you at trial (§ 42-4-1301(6)(d)). Police may take blood without consent only when there is probable cause for vehicular homicide, vehicular assault, criminally negligent homicide, or third-degree assault (§ 42-4-1301.1(3)).

"Persistent drunk driver" (PDD) is a designation, not a separate charge. You are a PDD if any one of four things is true: you drove with a BAC of 0.15 or more (even on a first offense); you refused chemical testing; you have two or more alcohol-related driving convictions or revocations; or you kept driving after an alcohol-related license restraint (§ 42-1-102(68.5)(a)). The designation adds no jail or fine of its own — the statute states that it does not affect the penalties imposed for the underlying driving offenses (§ 42-1-102(68.5)(b)). What it changes is the road back: a PDD must complete a level II alcohol and drug education and treatment program and hold an interlock-restricted license for at least two years after reinstatement (§ 42-2-126(4)(d)(II); § 42-2-132.5(3)). Note the separate 0.20 threshold: at 0.20 or more, a first offender’s jail minimum rises to ten days (§ 42-4-1307(3)(b)).

Yes. DUI and DWAI cover alcohol, "one or more drugs," and any combination — including marijuana, prescription medication, controlled substances, and inhalants (§ 42-4-1301(1)(a), (1)(b), (1)(d)). There is no per-se drug number: for marijuana, five nanograms or more of delta-9 THC per milliliter of whole blood gives rise to a PERMISSIBLE INFERENCE that you were under the influence — an inference a jury may accept or reject, not an automatic conviction (§ 42-4-1301(6)(a)(IV)). Being legally entitled to use the drug is no defense: that includes medical marijuana (§ 42-4-1301(1)(e)). The medical marijuana card cuts both ways procedurally — the prosecution cannot use your card in its case-in-chief, and the card alone is not probable cause for a blood draw (§ 42-4-1301(6)(j)-(k)). Drug testing under the express-consent law uses blood, saliva, or urine rather than breath (§ 42-4-1301.1(2)(b)).

A DEATH proximately caused by DUI is vehicular homicide, a class 3 felony (4 to 12 years presumptive plus 3 years mandatory parole, strict liability); if the driver was ability-impaired (DWAI) rather than under the influence, it is a class 4 felony (§ 18-3-106(1)(b), (1)(c)). SERIOUS BODILY INJURY caused by DUI is vehicular assault, a class 4 felony — class 5 if DWAI-based (§ 18-3-205(1)(b), (1)(c)). Both are separate crimes charged instead of, or alongside, the DUI itself — and both count as prior convictions that push a later DUI or DWAI toward the felony fourth-offense trigger (§ 42-4-1301(1)(a), (1)(j)). In these cases police may also compel a blood draw (§ 42-4-1301.1(3)). A driver UNDER 21 in the 0.02-to-0.05 band commits UDD — a class A traffic infraction first ($15-$100, up to 24 hours of public service), a class 2 traffic misdemeanor after that (10 to 90 days, $150-$300) — with 4 points and a 3-month/6-month/1-year revocation ladder; above that band, the full adult DUI/DWAI grids apply (§ 42-4-1301(2)(d); § 42-2-126(3)(b); § 42-2-127(5)(b)(IV)).