Two accountability stories involving the same officer

Former Gwinnett County Police Corporal Matthew Jordan Lau was terminated September 4, 2026, and charged with one count of Misuse of License Plate Data following a review of Flock Safety automated license plate reader searches. But just three days earlier, WSB-TV published an unrelated investigation into Lau’s DUI enforcement record. Those two developments must be examined separately: an alleged Flock offense is not proof that a DUI report was inaccurate, and reported DUI discrepancies do not establish guilt in the Flock case.

September 1: 65 DUI cases dismissed or reduced

WSB-TV investigative reporter Michael Seiden reported that Lau had been named Gwinnett County’s 2025 DUI Officer of the Year after making 175 DUI arrests in 2024. Yet the investigation found that 65 DUI cases involving Lau had been dismissed or reduced since April 2025. The reporting focused on discrepancies between descriptions of field sobriety test clues in reports and sworn affidavits and what body-camera and dash-camera footage appeared to show. A judge reportedly apologized to a defendant after examining one case.

The 65 figure combines dismissals and reductions; it does not mean 65 judicial findings of dishonesty or 65 exonerations. The full dispositions, motions, judicial findings and video recordings are needed to evaluate individual cases. This reporting raises serious questions about evidentiary reliability and supervisory review independent of the Flock matter.

WSB-TV investigation: DUI report and video discrepancies ↗

September 4: terminated and charged over Flock searches

Gwinnett County Police announced on September 4 that Lau faced one count of Misuse of License Plate Data and that his employment had been terminated. Former officer Derric Jaiquan Holmes was charged with six counts of the same offense and also terminated. The department additionally described the earlier case involving Renee Downer, arrested in May on simple battery and stalking charges, and confirmed termination of all three employees as part of its broader Flock-related review.

The department said the investigations remained active and additional charges could follow. The public announcement did not specify whose license plate Lau allegedly searched, how many queries his account made, what justification was entered, or whether data was shared. One criminal count should not be confused with exactly one database search; only original audit records can establish search frequency.

New safeguards followed access to audit tools in June

According to FOX 5 Atlanta, Gwinnett administrators gained access to a new auditing system in June 2026 that allowed them to examine search histories and flag questionable activity. Following the investigation, Police Chief J.D. McClure announced policy changes: searches would require reasons evaluated by supervisors, all officers would undergo retraining, and Flock data retention would fall from 30 days to 15 days.

That shorter retention period may reduce how long ordinary plate observations remain available, but it also makes preservation requests urgent. The actual retention settings for audit logs, search histories, exports and administrative records may differ from the retention period for captured plate data; they should not be assumed identical.

The POST record: employment, promotions and investigations

Historical Georgia POST materials obtained by Shields of Shame identify Lau as having first joined Gwinnett County Police in 2018, later returned in 2023, and became a corporal in January 2025. The materials identify him as a Field Training Officer and list his September 4, 2026 employment separation as Terminated. The historical profile shows File Review Required and two POST investigations.

These are historical administrative entries, not a verified live certification status. A POST investigation is not a revocation or a criminal conviction. The original supplied PDFs should be read for their separate details and dates; the current disposition of either investigation requires a fresh POST response.

Why the two investigations deserve separate document trails

For the Flock matter, the primary evidence is the native query audit: who logged in, which plate was searched, what case number and reason were supplied, when the query occurred and what results were accessed or exported. For the DUI matter, the primary evidence is each report and affidavit compared against the original body-camera, dash-camera and court recordings, together with prosecutors’ decisions and judicial rulings.

Combining the two stories without distinguishing the evidence could obscure both. They instead present an opportunity to examine whether the department’s supervisory systems detected problems in different areas of policing and how quickly it responded once concerns surfaced.

Case timeline

1. 2018: Lau first joins Gwinnett County Police, according to the historical POST material.
2. 2023: Returns to Gwinnett Police.
3. 2024: Makes 175 DUI arrests, according to WSB-TV.
4. January 2025: Promoted to corporal.
5. 2025: Recognized as the department’s DUI Officer of the Year for the preceding year’s arrests.
6. April 2025 onward: WSB-TV’s review identifies 65 DUI cases dismissed or reduced.
7. June 2026: Department gains new Flock auditing capability.
8. September 1: WSB-TV publishes the DUI evidence-discrepancy investigation.
9. September 4: Gwinnett announces Lau’s Flock misuse charge and termination, plus new Flock access safeguards.
10. October 12: No final Flock criminal disposition or later POST outcome independently verified in reviewed sources.

Related cases and independent sources

Original Shields of Shame Matthew Lau investigation ↗

FOX 5 Atlanta — audit findings and new safeguards ↗

CBS Atlanta — Gwinnett charges and terminations ↗

Atlanta Journal-Constitution — Flock policy changes and bond reporting ↗

WSB-TV — 65 DUI cases dismissed or reduced ↗

Institute for Justice — national ALPR abuse database ↗

Related SOS investigation — Derric Jaiquan Holmes ↗

Open-records requests: the complete investigative checklist

• Full native Flock audit for Lau’s user account: plate queries, timestamps, search reasons, case numbers, access roles, result views and exports
• Original suspicious-query alerts, reviewer notes, internal affairs referrals and supervisory approvals or exceptions
• Department Flock policies and signed acknowledgments before and after September 4, including June audit-tool activation details
• Original arrest affidavit, charging instrument, criminal docket, bond paperwork and any final court disposition
• Complete POST employment, certification, training and two-investigation records, including any final disciplinary orders
• List of DUI cases identified in the WSB-TV investigation, associated arrest reports, affidavits, video evidence, suppression motions, orders and dispositions
• Prosecutor notices, credibility disclosures, disciplinary findings and any Brady/Giglio-related determinations, where releasable
• Supervisor review policies and quality-assurance audits for DUI reports and body-camera evidence

Frequently asked questions

What was Matthew Lau charged with?

One count of Misuse of License Plate Data, according to Gwinnett County Police’s September 4 announcement.

Was he a corporal and Field Training Officer?

The supplied historical Georgia POST materials identify both roles.

Did 65 DUI convictions get overturned?

No. WSB-TV reported 65 DUI cases dismissed or reduced; that is not equivalent to 65 overturned convictions.

Was his certification revoked?

The supplied record lists File Review Required and two investigations. A final revocation has not been independently established.

Has he been convicted of Flock misuse?

No final criminal disposition was verified in the reviewed sources. Lau is presumed innocent unless proven guilty.

Updated October 12, 2026. Separate criminal allegations, employment actions, historical POST records and the WSB-TV DUI investigation are distinguished throughout this report.