What independent medical or police records exist about injuries from flash‑bangs at the Minneapolis protests?

1. University of Minnesota clinical review: the strongest independent medical dataset

An interdisciplinary team at the University of Minnesota reviewed electronic medical records from primary care, urgent care and emergency departments for May 26–June 15, 2020 and identified 89 patients whose visits were attributed to “less‑lethal” crowd‑control weapons, including projectiles and chemical irritants, using ICD‑10 codes and keyword searches of provider notes — this retrospective letter in the New England Journal of Medicine is the clearest, peer‑reviewed medical account tied to the Minneapolis protests ^{[1] [2]}.

2. What that study does — and does not — say about flash‑bangs specifically

The UMN review quantified injuries from rubber bullets, tear‑gas canisters, beanbag rounds and other projectiles (41 rubber‑bullet injuries, 7 tear‑gas canister injuries, 2 beanbag, 7 unknown), and flagged head, eye and traumatic‑brain injuries among patients, but its published summary aggregates “projectiles” and chemical irritants; it does not present a comprehensive, separately counted roster of injuries explicitly attributed only to flash‑bang (stun) devices in the NEJM letter format ^[1].

3. Local reporting and individual medical case records: corroborating injuries from stun devices

Multiple local news and watchdog reports document individual victims whose hospital diagnoses or medical treatment records link flash‑bang or stun‑grenade exposure to concussion, hearing loss, visual blurring and hospital transport — for example, a freelance reporter documented concussion and vision and auditory symptoms after a flash‑bang detonation, recorded in a hospital visit reported to the U.S. Press Freedom Tracker ^[4], and local TV reporting described children taken to hospital after a flash‑bang detonated near a family van ^[5].

4. Broader emergency‑department surveillance finds some flash‑bang cases but as a minority category

A separate ED surveillance study of the Capitol Hill Autonomous Zone protests and related 2020 incidents identified a small number of visits associated with flash‑bang grenades among crowd‑control weapon injuries, supporting the pattern that flash‑bang injuries are present but numerically fewer than injuries from chemical agents or projectile munitions in emergency‑department series ^[6].

5. The police records gap: policy exists but documentation has been limited or withheld

Minneapolis Police policy requires a report whenever less‑lethal projectiles are discharged and supervisory inquiries for injuries, yet public‑records requests produced little more than aggregated munitions‑count spreadsheets and not the incident‑level reports, and attorneys say many internal videos and investigative files have been shielded in litigation — a journalistic examination found the city supplied no detailed discharge reports to USA Today and that lawyers sought to keep bodycam and internal files sealed ^[3].

6. Interpretive balance: what the evidence supports and what remains unanswered

The independent medical evidence — peer‑reviewed hospital record reviews plus individual hospitalizations and reporter accounts — establishes that stun grenades and other crowd‑control devices caused concussions, hearing and vision problems and other injuries in Minneapolis protests, but the public medical datasets do not disaggregate every device type (flash‑bang versus blast ball versus projectile) comprehensively, and contemporaneous police operational records that would link each discharge to injuries are sparse or non‑public, leaving unanswered who fired each device, from what range, and whether policy was followed ^{[1] [4] [3]}.