In San Mateo Union High School Dist., et al. v. County of San Mateo, published January 31, 2013, the First District Court of Appeal, Division One, affirmed dismissal on demurrer of a suit the plaintiff school districts brought against a county and its former treasurer for $20 million in losses the districts sustained when the treasurer invested a pooled investment fund's money in notes issued by Lehman Brothers. The appellate court rejected the plaintiffs' argument that Government Code sections 27000.3 and 53600.3, which articulate the "prudent investor standard" governing investments by county treasurers, set forth a mandatory duty that would support a cause of action against the county under Government Code section 815.6. Since investment decisions are inherently discretionary, and those statutes set forth only general goals and guidelines rather than obligations to perform or not to perform specific acts, they did not create mandatory duties. The treasurer was immune from liability under Government Code section 820.2's discretionary immunity; and under Government Code section 815.2(b), that immunity extended to the county's liability for the treasurer's acts.
Another statute in the same scheme -- Government Code section 53601(k), which imposes a duty to invest in notes with a maximum remaining maturity of five years or less -- does impose a mandatory duty. But the statute did not apply, because it only applies to local agencies that do not pool money in investments with other local agencies. The statute that applied to pools -- section 53635 -- did not impose the maturity limit.
The above immunities did not apply to plaintiffs' cause of action for breach of contract. But the court concluded that, because the treasurer invested the funds given him to invest, the plaintiffs failed to plead breach of contract, and could not plead a breach.