Lawyers for Breathalyzer Challenge
Technical defense based on challenging the validity of breathalyzer test results.
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The breathalyzer test is the cornerstone of prosecution evidence in DUI cases. However, these devices are subject to strict regulatory requirements regarding calibration, maintenance, and administration protocols. Any deviation from these requirements can render the test result inadmissible, leading to case dismissal.
Legal Framework: Grounds for Challenge
Our technical defense examines: calibration records (breathalyzers must be calibrated periodically by authorized laboratories; expired or missing calibration records invalidate results), administration protocol (mandatory 15-minute observation period to prevent false positives from residual mouth alcohol, regurgitation, or recent drink consumption), measurement margin of error (±7.5% for evidential breathalyzers), and chain of custody (proper documentation of the device used, officers involved, and environmental conditions).
Defense Strategies
When the breath test is the sole evidence, a successful challenge effectively eliminates the prosecution's case. We request production of the full device maintenance log, officer training certifications, and video recordings of the testing procedure. In borderline cases (readings close to the 0.60 mg/l criminal threshold), the margin of error alone may be sufficient to create reasonable doubt.
Criminal Consequences
If the challenge does not succeed and the result stands, the drink-driving offence of Art. 379.2 CP carries, in the alternative, prison of 3 to 6 months, a fine of 6 to 12 months or community service, together with the deprivation of the right to drive of 1 to 4 years. For a first offence the prison term is usually suspended, so the licence deprivation tends to be the most onerous consequence. This is precisely why neutralising the breath result —or reducing it below the 0.60 mg/l threshold through the margin of error— is so decisive: it is the difference between a conviction and an acquittal.
Penalty Chart
| Type / Scenario | Criminal Penalty |
|---|---|
| Imprisonment | Prison sentences from 3 months to 6 years depending on severity and concurrence of offenses. |
| License Revocation | Revocation of driving privileges from 1 to 4 years. |
* Penalties shown are indicative. The actual penalty depends on case circumstances, applicable mitigating and aggravating factors.
Our Defense Strategy
Evidence Review
Comprehensive review of the prosecution evidence to detect procedural irregularities.
Negotiation
Limited plea agreement when the evidence is strong, to minimize consequences.
Road Safety Offences in Spain: DUI, Reckless Driving and Traffic Crimes — Defence Guide
Road safety offences (Arts. 379-385 CP) are among the most prosecuted in Spain. Driving under the influence (DUI), dangerous driving, unlicensed driving, and driving while disqualified carry not only prison sentences and fines, but also driving licence disqualification that can last up to 10 years.
Penalty Table: Road Safety Offences
| Offence | Article | Threshold | Penalty |
|---|---|---|---|
| DUI (alcohol) | Art. 379.2 | > 0.60 breath / 1.2 blood | 3-6 months prison or fine + 1-4 yr disqual. |
| DUI (drugs) | Art. 379.2 | Any detectable amount | 3-6 months prison or fine + 1-4 yr disqual. |
| Excessive speed | Art. 379.1 | +60 km/h urban / +80 km/h interurban over the limit | 3-6 months prison or fine + 1-4 yr disqual. |
| Reckless driving (Art. 380) | Art. 380 | Manifest disregard for life | 6 months – 2 years + 1-6 yr disqual. |
| Unlicensed driving (never held) | Art. 384 | No licence ever held | 3-6 months prison or fine |
| Driving while disqualified | Art. 384 | Lost by judicial/admin order | 3-6 months + 1-4 yr further disqual. |
| Hit and run (Art. 382 bis) | Art. 382 bis | Leaving accident scene | 6 months – 4 years |
Key Defence Strategies
Challenge the Breathalyser Result
Breathalyser devices must be calibrated and certified. Challenge: calibration records out of date, device malfunction, improper administration protocol (required 15-minute observation period before test).
Drug Test Challenge (Saliva/Blood)
Roadside saliva tests are presumptive, not conclusive. Request the blood confirmatory test. If the confirmatory test was not performed or the result is contested, the evidence may be insufficient.
Reckless Driving: subjectivising the risk
Art. 380 requires manifest, concrete endangerment of road users. Driving fast on an empty road at night may not constitute the 'manifest danger to life' required.
Disqualification Computation
If the accused drove believing the disqualification had expired (administrative error, incorrect notification), the subjective element of Art. 384 may be absent.
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