International law firm Mayer Brown has added a new attorney to its Houston office, according to a press release.

Shawn O’Brien joins the tax controversy practice of Mayer Brown, having previously managed a similar practice group in Jackson Walker’s Houston office.

“Shawn has a proven track record of handling complex, cutting-edge tax disputes, and he represents clients on various significant tax issues before the IRS as an advocate in trial and appellate litigation,” partner Joel Williamson of Mayer Brown’s tax controversy practice said in a statement. “His experience with a wide range of tax controversy issues and tax transactions, particularly within the energy industry, further expands the reach of Mayer Brown’s prominent tax controversy and transfer pricing practices to Texas, one of the most important markets in the United States.”

The new legal job provides O’Brien a platform from which to offer clients top level experience and credentials in cross-border tax matters.