With 29 years at the U.S. Attorney’s Office under his belt — 25 of them as chief of the tax division — Jay Weill is ready to take on tax disputes from the flip side.

Earlier this month, the former prosecutor moved into private practice, joining San Francisco’s Sideman & Bancroft as a partner. Well-regarded among tax lawyers, Weill has spent his career defending and prosecuting civil tax cases and prosecuting criminal cases in the Northern District.