Guardian Interlock: what people actually report
We do not take payment for placement, and we do not run a star rating we cannot defend. What follows is what we can verify.
What we can verify
- Network: 207 installation points across 10 states — 2% of the 10,531 we index, #7 by size.
- Reach into smaller towns: present in 180 towns and cities. This matters more than the headline number, because you drive to a center every 30 to 60 days for calibration.
- How easily you can leave: 81% of its addresses also fit a competitor’s device — switching provider often means staying at the same garage.
- Where you have no alternative: in 5 towns it is the only installer we found. Local monopoly is not a criticism of the company, but it does mean no second quote.
- Published pricing: no national price list; quotes are given per state and per center.
- Not available in: Alaska, Alabama, Arkansas, Arizona, Connecticut, District of Columbia, Delaware, Georgia, Hawaii, Iowa, Illinois, Indiana, Kansas, Louisiana, Maine, Michigan, Minnesota, Missouri, Mississippi, Montana, North Carolina, North Dakota, New Hampshire, New Jersey, Nevada, New York, Ohio, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, Vermont, Washington, Wisconsin, West Virginia, Wyoming.
How to read this
Every figure above is counted from our own index of installation points, rebuilt from the providers’ public center finders. It describes reach and structure — not how the company treats you when a test fails at 7am. Those two things are often unrelated, and anyone claiming to score them from the same data is guessing.
What has been put to Guardian Interlock by a regulator or a court
This is the part of a provider’s conduct that leaves a public, dated, checkable record. Forum posts do not. Each entry below names the legal entity involved, the forum, the docket where there is one, and how it ended — including the ones the company won, because a review that prints only the losses is an advert with the sign reversed.
Whether a statutory fee cap caps the whole bill
Oklahoma law caps the monthly interlock maintenance fee at $25. The driver was paying $39 in lease, $25 in maintenance, $5.41 in sales tax and a $5 damage waiver, and argued the cap had been exceeded. The Attorney General filed against the company's reading of the statute.
Outcome. The company won. On 23 February 2016 the court held that the $25 cap covers maintenance only, and does not limit rental, tax or damage-waiver charges. The practical lesson runs well beyond Oklahoma: a capped fee is not a capped bill, and the cap you read about may cover one line of several.
Guardian Interlock Network, Inc. · Heath v. Guardian Interlock Network, 2016 OK 18 · Oklahoma State Courts Network, Heath v. Guardian Interlock Network · checked 2026-08-30
Decertification by the state, and the company's suit over it
Minnesota decertified the company in October 2015 and required it to pull every device out of vehicles in the state. Guardian sued the Department of Public Safety for breach of contract, saying the state applied a photo-capture performance standard that was not in the contract and then changed how it was measured.
Outcome. Reported at the time as a pending suit for damages and a restraining order. We have not found a published decision, and record this as the dispute it was rather than as an outcome.
Guardian Interlock Systems · Star Tribune, contemporaneous report · checked 2026-08-30
What we looked at, and what a blank section means
We searched published court decisions and federal dockets, state attorney general enforcement records and contemporaneous reporting on those cases. Where a provider has no entries below, it means we found nothing in those places — not that nothing exists. Small claims, arbitration and private complaints leave no public record at all, and the industry writes arbitration into its agreements, so a quiet record is partly a feature of how these contracts work.