HAYWARD — Hayward police Chief Diane Stuart is abruptly retiring nearly four months after the city placed her on administrative leave and launched an investigation into her handling of the department, according to a joint Wednesday statement from the city and Stuart.

Related Articles Husband of former Hayward police chief bashes city investigation Her retirement is effective immediately, according to the joint statement, which neither stated why she was retiring nor detailed the outcome of the city’s investigation.

McAdoo praised Stuart’s “ability to maintain and strengthen” the police department’s top ranking with the national Commission on Accreditation for Law Enforcement Agencies. McAdoo also credited Stuart for her “successful relationship building with the Hayward community during challenging national conversations about law enforcement’s use of force.”

The city acknowledged it received an anonymous letter that made “allegations regarding the chief’s administration of the police department” but did not say in the joint statement when the letter was received. Stuart, however, had not seen the investigation or letter as of Wednesday, according to the city statement.

“While this decision moves up Chief Stuart’s planned retirement by about four months, the chief and the city manager believe it is in the best interest of the men and women of the Hayward Police Department, as well as to the community she has served, to retire at this time and allow the department and community to move forward under the leadership of the new city manager,” the statement read. “Chief Stuart’s only interest is to ensure that members of her department are able to continue serving the Hayward community safely and without the unfortunate distractions of the last few months.”

Hayward City Manager Kelly McAdoo abruptly placed Stuart on administrative leave in late August and launched the personnel investigation. Very few details of that investigation, however, have been released by city leaders.

Capt. Mark Koller was subsequently appointed by McAdoo to serve as the acting police chief while the investigation took place. McAdoo said he will continue to serve in that role until a decision is made on the recruitment process for a new police chief.

McAdoo said on Wednesday that the city will release the investigation results for Stuart to review at a mutually agreeable time. She declined to say when the investigation was officially complete, citing public disclosure protections for law enforcement employees.

“State law protects the privacy interests of personnel information regarding all law enforcement officials, and the city is prohibited from disclosing details of all law enforcement officers,” the city’s joint statement read.

Stuart previously served in the San Jose Police Department for 26 years, rising to the rank of assistant chief, before joining the Hayward Police Department as its chief in 2011.