Sen. Sherrod Brown, D-Ohio, sent a letter to the Office of the Comptroller of the Currency Tuesday asking the agency to reform its policies governing how banks treat homes abandoned prior to foreclosure. Specifically, Brown raised concerns with guidance the OCC released in December. The regulator said banks would be allowed to release a lien securing a defaulted loan rather than foreclosing on the property. The OCC left it to the bank to determine when it could do this and even warned banks about the risks of making this decision. "While the financial risk must be considered, banks and servicers should also consider the potential for reputation and litigation risk arising from their position as a prior mortgagee or servicer of a now-abandoned property," the OCC said. The Government Accountability Office released a report in 2010 showing many struggling city and state governments were left to pay high costs when a bank releases the lien. Las Vegas and Chicago passed ordinances forcing lenders to maintain vacancies. Brown recently introduced a bill that would make new servicing reforms federal law, but it is still tied up in Congress. In his letter to Acting Comptroller of the Currency John Walsh, Brown cited one study that estimated eight Ohio cities had to pay more than $13 million to address or maintain all vacant properties in 2006. Cleveland, the senator said, lost more than $6.5 million in delinquent property taxes on abandoned homes that year. "This practice, also known as an 'abandoned foreclosure' or a 'bank walkaway,' has caused substantial harm to Ohio's communities and should not be supported by the federal government," Brown wrote. He said the OCC should require mortgage servicers to pay for demolishing a property or transfer the title of an abandoned home to the local government or a nonprofit. "Leaving these properties vacant — creating healthy and safety hazards and sticking Ohio communities with the bill — should happen rarely, if at all," Brown said. Write to Jon Prior. Follow him on Twitter @JonAPrior.