GOP Senate candidate Dan Winslow recently promised to release 10 years of tax returns and called on his opponents to do likewise. But even in making good on that vow, Winslow showed the ambivalence that many candidates feel about financial disclosure; his campaign invited reporters to inspect documents late on Friday afternoon — the time of week when politicians put out information in the hopes of minimizing news coverage. Meanwhile, GOP rival Michael Sullivan has vowed to release his returns, but hasn’t said when; Gabriel Gomez has been noncommittal on the issue.

In fact, all five Senate candidates, Republicans and Democrats, should provide tax information as a demonstration of openness. Voters should know how candidates for high public office are earning their money, and the financial disclosure forms that federal officeholders must complete provide too limited a picture.