The fatal killing of 13 year old Andy Lopez by Sonoma County sheriff's deputy Erick Gelhaus took place on October 22, 2013. Lopez was carrying an airsoft gun and Gelhaus opened fire on Lopez, mistaking the airsoft gun for a real firearm.

The Sonoma County Board of Supervisors created IOLERO as an independent, non-police agency to audit Sheriff’s Office Internal Affairs, make policy recommendations, and (as later expanded) investigate whistleblower complaints and critical incidents. [1] 

Measure P passes; unions file labor charges. Voters approved Measure P, expanding IOLERO’s authority (including subpoenas) and minimum funding. The Deputy Sheriffs’ Association (DSA) and SCLEA filed unfair-practice charges at PERB, claiming the County failed to meet-and-confer before placing the measure on the ballot. [2] 

PERB Decision 2772-M (vacated in part on appeal). PERB ruled the County violated meet-and-confer duties and purported to sever/void certain Measure P provisions as to represented employees; the County appealed. [3] 

The First District held PERB skipped an initial “significant and adverse effect” analysis (Claremont test) and exceeded its authority by invalidating Measure P; it remanded to PERB to determine which ballot-placement decisions/effects, if any, were within scope and required bargaining. [4] 

David Peláez-Chavez was fatally shot by Deputy Michael Dietrick after a 45-minute chase through rough terrain. Dep. Dietrick claimed he feared Mr. Peláez-Chavez was going to throw a rock at him. Dep. Powers almost simultaneously shot Mr. Peláez-Chavez with his taser.

PERB concluded the County failed to give the unions adequate notice/opportunity to meet-and-confer before the Board placed Measure P on the ballot; ordered cease-and-desist and posting (no wholesale voiding). [5] 

The County and law-enforcement labor groups executed LOAs that spell out IOLERO’s oversight authority (auditing investigations, access to materials, etc.), resolving many meet-and-confer issues tied to Measure P. [6] 

Sonoma County District Attorney Carla Rodriguez issued her report of investigation in which she concluded criminal charges were not warranted against Dep. Dietrick or Dep. Powers for the death of David Peláez-Chavez.

IOLERO issued subpoenas in a Sheriff’s Office whistleblower matter and moved in Sonoma County Superior Court to enforce them; in Sept. 2024 the court ruled IOLERO lacked statutory authority to subpoena in whistleblower investigations (distinct from other contexts). IOLERO appealed in Nov. 2024; the dispute remained active into 2025. [7] 

The County’s IOLERO news page references expansion of audits while appealing the ruling limiting subpoena power in whistleblower cases. [8] 

During IOLERO’s investigation of the July 2022 David Peláez-Chavez shooting, the DSA accused IOLERO of overreach and filed a harassment complaint; sealed court subpoenas from the whistleblower case were inadvertently released, drawing new scrutiny. IOLERO’s Community Advisory Council set a special meeting for Oct. 22, 2025 to discuss a response. [9]

IOLERO issued its report on the Peláez-Chavez killing. IOLERO could not reach conclusions on some of the issues because Sheriff's officers refused to answer questions for IOLERO and Sheriff Engram refused to issue Lybarger admonitions which would have forced them to answer questions while protecting their statements from use in criminal proceedings.

A state appellate court has tentatively ruled that Sonoma County’s civilian law enforcement watchdog agency can issue subpoenas to deputies as part of its whistleblower investigations into the Sheriff’s Office.

[1] Sonoma County Board of Supervisors Ordinance establishing IOLERO, 2015. [2] PERB Case Nos. SF-CE-1640-M and SF-CE-1641-M, filed 2020. 

[3] PERB Decision 2772-M (June 23, 2021). 

[4] County of Sonoma v. PERB (2022) 80 Cal.App.5th 167. 

[5] PERB Decision 2772a-M (February 28, 2023).

[6] Sonoma County Human Resources LOA summary, May–October 2023. 

[7] Sonoma County Superior Court, IOLERO v. Sonoma County Sheriff’s Office, Case No. SCV-275113, 2024. 

[8] Sonoma County IOLERO public updates, December 2024. 

[9] CLEAN response and DSA complaint correspondence, September–October 2025.