---
title: "How is Illinois breath evidence suppressed?"
description: "Illinois breath evidence is suppressed by defeating foundational proof required under 625 ILCS 5/11-501.2 and 20 Ill. Adm. Code 1286. Grounds include lack of a valid operator permit, expired..."
url: https://chicagoduilawyer.net/faq-items/how-is-illinois-breath-evidence-suppressed/
date: 2026-07-08
modified: 2026-07-08
author: "Chicago DUI Lawyer"
type: faq
lang: en
---

# How is Illinois breath evidence suppressed?

Illinois breath evidence is suppressed by defeating foundational proof required under 625 ILCS 5/11-501.2 and 20 Ill. Adm. Code 1286. Grounds include lack of a valid operator permit, expired instrument certification, missed accuracy checks, broken 20-minute observation, RFI interference, mouth alcohol from GERD, dentures, or recent ingestion, and instrument malfunction. Constitutional grounds attack the underlying stop and arrest. Warning to Motorist deficiencies affect refusal cases. A written motion cites specific administrative rule violations and attaches subpoenaed records. A granted motion strikes the numerical BAC entirely, often collapsing the state's per se case and forcing a plea reduction or dismissal. A Chicago DUI lawyer files early to preserve the record.