The chair of Philadelphia's police oversight board has been arrested and charged with selling sensitive witness information to an inmate who had expressed intentions of violence, authorities announced Tuesday.

Robert T. Grim, who heads the Police Advisory Commission, is accused of providing the name and location of a witness in a criminal case to an inmate who had vowed to "blow down" the witness. The information allegedly sold by Grim was related to an ongoing criminal investigation, although the specific details of that case have not been fully disclosed.

According to the Philadelphia District Attorney's Office, Grim accessed confidential information and then shared it with the inmate, identified as Jonathan Walker. Prosecutors stated that Walker had made threats against the witness, indicating a potentially dangerous situation. The alleged transaction occurred earlier this year, prompting an investigation by the District Attorney's office.

The charges against Grim include obstruction of justice, official oppression, and disclosing confidential information. These allegations cast a shadow over the integrity of the city's police oversight mechanisms and raise serious questions about the security of sensitive case details.

Prosecutors detailed that Grim allegedly met with Walker's associate and provided the witness's information. The inmate, Walker, is currently incarcerated and facing separate charges. The motive behind Grim's alleged actions remains under investigation, but the connection to potential witness intimidation is a central focus.

Mayor Jim Kenney's office stated they were aware of the charges and are monitoring the situation closely. The Police Advisory Commission is an independent body tasked with reviewing police conduct and making recommendations for improvement, making the chair's alleged actions particularly concerning.

Grim's arrest has sent ripples through the city's legal and law enforcement communities. The Police Department has not directly commented on the charges but has pledged full cooperation with the District Attorney's investigation. The case highlights the challenges in maintaining both transparency and security within the justice system.

This incident follows a period of heightened scrutiny on law enforcement and oversight bodies nationwide, particularly in the wake of events like the murder of George Floyd, which led to increased calls for accountability. The charges against Grim present a new challenge for Philadelphia's efforts to reform and build trust in its public safety institutions.