The D.C. Board of Elections and Ethics yesterday blocked an initiative from the Sept. 9 ballot that would have asked voters whether the District of Columbia should become the nation's 51st state.

The initiative would have been the first of four steps in a process by which Congress can add states to the union.

Supporters of the statehood drive had collected 21,982 signatures -- well over the 12,451 necessary to qualify the measure for the ballot -- but the board ruled that the measure, as drafted, was "not proper subject matter" for an initiative.

Hilda Mason, an at-large City Council member and the Statehood Party's only current officeholder, said supporters of the initiative would challenge the board's ruling in the D.C. Court of Appeals.

The action came despite a recommendation by the board's general counsel, William H. Lewis, that the initiative he accepted and the process of certifying petition signatures be started.

The initiative, if approved by D.C. voters, would have authorized a convention to draft a new state constitution and a special election to choose delegates to that convention. After the constitution was drafted, another election would have been held to ratify or reject it. Then the document would have been presented to Congress, and a simple majority of both houses could have admitted the District of Columbia as a state.

Backers of the initiative argued that this process was more likely to secure voting representation in the U.S. Senate and House of Representatives than the D.C. Voting Rights Amendment, which has been ratified by only nine of the 38 state legislatures needed for the amendment to become law.

The elections board ruled that the initiative appeared to violate the city's home rule charter by, in effect, appropriating funds, since money would be required to convene the constitutional convention.

The board also objected to the fact that backers of the measure submitted a number of amendments after the petitions had already been filed, meaning that those who signed were unaware of the changes.

Supporters argued that the short summary statement heading the petition sheets was unchanged, and that the amendments were technical.