One of the few victories in the climate policy arena last decade was the passage of California's pioneering climate law in 2006. It called for, among other things, establishing a cap and trade system to limit greenhouse gas emissions from the state's largest polluters. It's seen a long and winding road since then -- a tough campaign was waged by industrial interests and out of state oil companies to overturn the bill last year. It survived, but now a federal judge has suspended the law once again -- this time at the behest of local environmental activists. What gives? Local activists want it to be even tougher on particulate pollution. The Times explains.