Alameda County vowed answers in Sophia Mason’s death. Nearly 3 years later, none have come.

OAKLAND — Under a haze of secrecy, a county investigation into the death of 8-year-old Sophia Mason — whose malnourished body was found decomposing in a basement bathroom — has dragged on for nearly three years.

Now, even as hints emerge that the 2023 county-ordered probe may finally be wrapping up, child welfare and open governance experts say the delay in completing it raises new alarms about the county’s commitment to keeping children safe.

They say the reason cited by county officials for holding up the investigation ...