Calpers’s investment chief resigned from the biggest US pension fund on 5 August amid questions about potential conflicts of interest raised by his personal investments. Now board members are calling for an inquiry into the fund’s handling of the matter.

Several members of the 13-person board are asking when California Public Employees’ Retirement System chief executive Marcie Frost learned that the pension fund, under former investment chief Ben Meng, steered money into a firm in which he was personally invested.