DUI Evidence Suppression Motion

Summary:

A DUI evidence suppression motion is a critical pretrial tool that challenges unlawfully obtained evidence in drunk driving cases. For individuals facing DUI charges in California, successfully suppressing key evidence (like breathalyzer results or field sobriety tests) often leads to reduced penalties or outright dismissal. The immediate consequences include avoiding license suspension, jail time, and fines, while long-term impacts affect employment opportunities, insurance rates, and professional licensing. Unique legal challenges hinge on Fourth Amendment violations, inaccurate testing protocols, and procedural errors during arrests. Commercial drivers and professionals with occupational licenses face particularly severe collateral damage from DUI convictions.

What This Means for You:

• Immediate Action: Request a DMV hearing within 10 days of arrest to contest license suspension (California Vehicle Code §13558). Simultaneously, hire a DUI attorney to file a suppression motion before your arraignment, citing Fourth Amendment violations under the U.S. Constitution.
• Legal Risks: Conviction risks include up to 6 months in jail (first offense), $1,000+ fines, 6-month license suspension, and mandatory DUI school (California Penal Code §23536). Aggravating factors like BAC ≥0.15% or prior offenses escalate penalties to felony charges with multi-year prison terms.
• Financial Impact: Beyond $10,000+ in attorney fees, expect $2,000 annual insurance increases, $150/month ignition interlock costs, $600 DUI program fees, $125 license reinstatement fees, and lost wages from court appearances or jail time.
• Long-Term Strategy: Pursue expungement after probation completion (California Penal Code §1203.4), secure restricted “work licenses” during suspension periods, and disclose convictions transparently to mitigate employment/licensing repercussions. Consider civil lawsuits for wrongful arrests.

Explained: DUI Evidence Suppression Motion:

A suppression motion under California Penal Code §1538.5 asks the court to exclude evidence obtained through unconstitutional police actions. Federally, the Fourth Amendment prohibits unreasonable searches/seizures, requiring probable cause for traffic stops and chemical tests. In California, implied consent laws (Vehicle Code §23612) mandate BAC testing but require officers to properly advise drivers of consequences for refusal. Motions often target breathalyzer calibration records, blood draw chain-of-custody errors, or lack of reasonable suspicion for initial stops.

Successful suppression hinges on proving officers violated procedural safeguards. For example, warrantless blood draws without exigent circumstances violate Missouri v. McNeely (2013), while improperly administered field sobriety tests lack scientific validity per People v. Kelly (1976). If granted, suppressed evidence cannot be used at trial, frequently forcing prosecutors to dismiss charges.

Types of DUI Offenses:

California recognizes standard misdemeanor DUIs (Vehicle Code §23152) and felony “wet reckless” charges with priors. Aggravated DUIs under Vehicle Code §23578 involve BAC ≥0.15%, child endangerment, or accidents causing injury. Commercial drivers face stricter 0.04% BAC limits (Vehicle Code §34500), while underage drivers (under 21) violate Zero Tolerance laws at ≥0.01% BAC (Vehicle Code §23140).

Unique variations include DUI-drugs (Health & Safety Code §11550) requiring drug recognition expert (DRE) testimony, and boating DUIs (Harbor & Navigation Code §655). All types trigger separate DMV actions under the Administrative Per Se (APS) license suspension program.

Common Defenses for DUI:

Suppression motions form the cornerstone of DUI defense. Attorneys typically challenge the initial traffic stop’s legality (e.g., faulty equipment justifying pullovers), lack of Miranda warnings during custodial interrogation, or failure to observe 15-minute monitoring periods pre-breath test. Medical defenses like acid reflux (causing mouth alcohol skewing breath results) or ketogenic diets (producing false-positive acetone readings) undermine BAC validity.

Blood test defenses attack chain-of-custody gaps, fermentation in vials, or improper anticoagulant use. Field sobriety test challenges cite non-standardized administration or disabilities affecting performance. Rising blood alcohol arguments prove BAC was below 0.08% during driving but increased by test time.

Penalties and Consequences of DUI Offenses:

First-offense misdemeanor DUIs carry up to 6 months jail, $390-$1,000 fines (plus penalty assessments tripling costs), 6-month license suspension, and 3-month DUI school. Second offenses within 10 years mandate 96 hours to 1 year jail, 2-year license revocation, and 18-month DUI school.

Felony DUIs (3+ priors, injury-causing crashes) incur 16 months to 4 years state prison, 4-year license revocation, and $5,000 fines. Collateral consequences include 10-year immigration status issues, 7+ years on criminal records, and professional license suspensions for nurses, pilots, or attorneys.

The DUI Legal Process:

Post-arrest, defendants face dual tracks: (1) A DMV hearing within 10 days to contest license suspension, and (2) criminal arraignment where suppression motions must be filed pre-plea. At pretrial conferences, attorneys negotiate plea deals based on suppressed evidence viability. If motions succeed, trials often get dismissed; if denied, cases proceed to jury trials where reasonable doubt defenses target remaining evidence gaps. Post-conviction, sentencing includes mandatory ignition interlock installations (AB 91 pilot counties) and probation terms.

Choosing a DUI Attorney:

Select California State Bar-certified criminal law specialists with 100+ DUI trials and local courthouse rapport. Prioritize attorneys trained in breathalyzer maintenance (Title 17 compliance) and blood retesting protocols. Flat-fee structures ($3,500-$15,000) are preferable to hourly billing. Verify past successes via published appellate rulings (e.g., People v. Williams suppression wins) and Avvo client reviews.

Other DUI Resources:

National Highway Traffic Safety Administration (NHTSA) standards for field sobriety testing: nhtsa.gov
California DMV APS hearing guide: dmv.ca.gov

People Also Ask:

Q: Can police stop me without probable cause for a DUI checkpoint?
California checkpoint stops require advance publicity, neutral site selection, and uniformed officers – deviations invalidate arrests per Ingersoll v. Palmer (1987). Non-random stops (e.g., targeting specific cars) allow suppression motions.

Q: Do I have to take a roadside breathalyzer test?
California’s implied consent law mandates post-arrest chemical tests, but preliminary alcohol screening (PAS) tests are optional for non-probationers (Vehicle Code §23612(h)). Refusing PAS cannot justify arrests but may lead to field sobriety tests.

Q: Can I suppress breathalyzer results for machine malfunctions?
Yes. California Title 17 requires quarterly calibrations, 0.08% +/- 0.01% accuracy tolerances, and certified operators. Unmaintained devices or expired solutions render results inadmissible.

Q: How long does a suppression motion take?
Motions typically require 2-3 court hearings over 60-90 days. Evidence hearings involve officer cross-examinations and forensic expert testimony, with rulings issued within 15 days post-hearing.

Q: Does suppression guarantee my case gets dismissed?
Not always. Prosecutors may proceed with remaining evidence (e.g., witness testimony), but dismissals occur when suppressed evidence was central to proving BAC or impairment.

Expert Opinion:

Filing a suppression motion is the most effective way to dismantle a DUI case pre-trial, as over 30% of convictions hinge on evidence vulnerable to constitutional challenges. Neglecting Fourth Amendment violations risks irreversible criminal records and license sanctions that devastate livelihoods for decades.

Key Terms:

• Fourth Amendment unconstitutional search motion California
• DUI breath test suppression legal grounds
• DMV APS hearing license suspension defense
• California Penal Code 1538.5 evidence exclusion
• Field sobriety test reliability challenge

*featured image sourced by DallE-3