A Chicago police officers’ pension fund has filed suit against Bank of America and U.S. Bancorp, claiming that the two banks failed to protect investors during their turn as MBS trustees and violated an obscure, seven-decade-old federal securities statute. The lawsuit, brought last week by the Chicago Policeman’s Annuity & Benefit Fund, said that BofA, and later U.S. Bank as successor trustee, “regularly disregarded their contractual and statutory duties” by failing to oversee some 41 Washington Mutual trusts backed by home loans. “By failing to perform their duties, defendants have caused MBS holders...