The chief of the state Board of Insurance has been placed on leave while the board investigates allegations of foot-dragging in the largest insurance company insolvency case in Texas history. The board also said Thursday that the Travis County District Attorney's Office will review the agency's handling of the National County Mutual Fire Insurance insolvency case for any criminal wrongdoing. National County Mutual, a Dallas company with 125,000 auto insurance policyholders statewide, was declared insolvent last week and taken over by the insurance board. The company was $54 million in the debt. The board said recent criticism prompted it to initiate the investigation into the department's delay in taking control of National County Mutual. Several lawmakers complained the insurance board's staff knew of the company's problems since at least 1986 and should have moved earlier to protect its policyholders. During the examination, Commissioner Doyce Lee will be placed on leave, board members said. Board members said Lee recommended doing the independent audit and contacting the district attorney. But they said complaints by state lawmakers and consumer interest representatives forced them to put him on leave. Lee, 47, commissioner since 1985, said he agreed with the decision. ``I think it takes the pressure off of me and the board, and the agency can go about its business of regulating the industry. That will give time for the air to clear,'' he said. State Rep. John Gavin, D-Wichita Falls, chairman of the House Insurance Committee, supported the board's action. ``Most of the problem seems to be a lack of communication within the agency. The left hand and the right hand don't seem to work very well together,'' he said. Insurance board members attribute many of its problems to a major reorganization of the agency and rapid expansion of the staff, from about 850 employees to 1,300 in the past 18 months.