The Washington Supreme Court on Thursday blocked the attorney general’s office from releasing certain financial information related to the investigation of a mortgage company, in a case that balanced federal privacy laws with the state Public Records Act. A lawyer who handles predatory lending cases filed a Public Records Act request for documents related to the investigation into the lending practices of Ameriquest Mortgage Co. Attorney General Rob McKenna was prepared to release certain information — including customer names, addresses, phone numbers and interest rates — that Ameriquest provided during the investigation. The attorney general’s office argued that much of the information was already available in the public record, and thus fell within an exception in the privacy laws, which might otherwise prevent its release.