This is an unusual 4-3 split opinion by the California Supreme Court. Unlike the United States Supreme Court, you don't routinely see such sharply split opinions from that tribunal.
Plus, given the underlying topic, it's an unusually sharp dissent. Still generally moderate in tone, but the case is a hypertechnical one about "the job classification and salary-setting authority granted to public pension boards and county boards of supervisors." Not exactly a high-profile, hot button topic.
The majority opinion is by Justice Corrigan, and the dissent is by Justice Groban. Justice Simons, sitting by designation from the 1/5, is the (exciting) swing vote.