The Arizona law, which requires police "when practicable" to detain people they "reasonably" suspect to be in the country illegally, has drawn widespread condemnation from immigration and civil rights advocates, and many elected officials, including President Obama.
Some of the law's opponents gathered in San Francisco this morning to send off a caravan of people to Phoenix, where a rally is scheduled for Saturday at the state's Capitol as part of a national day of action against the legislation.
About 100 community and labor organizers left in a large bus and a handful of passenger vans this morning, according to Mariana Viturro, a spokeswoman for the group.
Viturro said the group has been in touch with organizers in Phoenix, who expect at least 50,000 people to attend Saturday's rally.
Black clergy members are also traveling from the Bay Area to Phoenix for the rally, according to Jackie Wright, a spokeswoman for the Northern California Interreligious Conference.
The members include the Rev. Phil Lawson, founder of the Oakland-based Black Alliance for Just Immigration, the Rev. Gregory Brown, pastor of the Miracles of Faith Community Church in Oakland, and the Rev. Jethroe Moore, president of the San Jose/Silicon Valley Chapter of the National Association for the Advancement of Colored People.
"They're marching in solidarity with other people around the country to protest the Arizona law that is discriminatory and a threat to liberty for everyone," Wright said.
"There are black clergymen standing with the Latino community, which harkens back to the civil rights era when people used to go down South in support of black people experiencing the injustices of Jim Crow," she said.
The San Francisco Giants are also hosting a weekend series against the Arizona Diamondbacks, and activists are planning to protest outside AT&T Park tonight and Saturday.
Along with protests outside the game tonight, a march is planned at 4 p.m. Saturday that will start at Justin Herman Plaza end outside the baseball stadium, where the two teams are playing a game scheduled to start at 6:05 p.m.
Beginning at about 5:15 p.m. Saturday, protesters will gather outside AT&T Park, where Viturro said "we are going to educate fans about (the law) and are asking to boycott the game."