Professor Jonathan Stewart has been appointed or re-appointed to several committees that set or impact policy related to the identification or mitigation of earthquake risk. He was recently reappointed as a member of the University of California Seismic Advisory Board, which is developing collapse risk estimates for buildings at UC campuses to guide retrofit decisions in accordance with UC policy.

Stewart was also recently appointed to the Building Seismic Safety Council Provisions Update Committee (PUC), which drafts the National Earthquake Hazards Reduction Program (NEHRP) Provisions and Commentary on six-year cycles; these are sources for national building code documents.

Finally, he was recently re-appointed to the Advisory Committee on Earthquake Hazards Reduction (ACEHR), which provides input to and reviews NEHRP federal agencies, like the National Institute of Standards and Technology (NIST), US Geological Survey (USGS), and the National Science Foundation (NSF).