As the presidential campaign narrows and its costs skyrocket, detailed disclosure of financial resources becomes ever more important. Of the leading contenders, so far, only Senator Barack Obama has released his full income-tax returns -- a level of disclosure once routine for candidates after the political corruption of Watergate.
Release of the tax returns should not be made conditional on winning the nomination, as Senator Hillary Rodham Clinton has made it. Both Senator John McCain, the Republican front-runner, and she owe it to their parties and to voters to promptly make available their Internal Revenue Service filings, and to respond to any questions about them. It is true that as senators, Mrs. Clinton and Mr. McCain are required to file financial disclosure forms. But those forms present only general parameters of family financial resources, not the detail available on tax returns.