SAN FRANCISCO (KRON) — As San Francisco’s Millennium Tower continues to sink and lean, questions are now being raised as to whether the city’s building department dropped the ball in its oversight of the building’s development.

For several hours, San Francisco Supervisor Aaron Peskin played the role of prosecutor, grilling members of San Francisco’s Department of Building Inspection about the Millennium Tower.

The 58-story project is located at 301 Mission Street. Peskin says it has so far sunk 16 inches and is leaning 2 inches.

At the hearing, Peskin questioned how in 2004, the building department could deny a similar project a few hundred feet away at 80 Natoma after it was projected to sink 11 inches.

Peskin also suggested the building department should have pushed harder to require a geotechnical engineer review the Millennium Tower and questioned why a draft report issued by a peer review panel in 2014 raised concerns, only to have them wiped away in a 2016 final report.

Watch the above video to see Dan Kerman’s full report.