Mexican President Enrique Pena Nieto is scheduled to address state lawmakers as he finishes a two-day visit to California, but not all members of the Legislature are in a welcoming mood.
At least three Republicans have rejected Tuesday's lunch invite from Gov. Jerry Brown to protest Mexico's incarceration of a Marine.
State Assemblyman Tim Donnelly, a former gubernatorial candidate, is joining a protest outside the historic Stanford Mansion, where the lunch will be held, demanding the release of former U.S. Marine Sgt. Andrew Tahmooressi.
Mexican officials say they found a rifle, shotgun, pistol and hundreds of rounds of ammunition in the pickup truck driven into Mexico by Tahmooressi on April 1.
Supporters say Tahmooressi made a wrong turn into Mexico and was detained.
Other Republicans have criticized the plans to protest.
Later Tuesday, Pena Nieto will address a joint-session of the Legislature.