A voter heads to a polling precinct at Central United Methodist Church before noon Tuesday, Nov. 6, 2012.

Topeka ? A federal judge this week refused to issue a temporary restraining order to block the U.S. Election Assistance Commission from issuing new federal voter registration forms for Kansas and two other states that ask voters to show proof of U.S. citizenship.

Judge Richard J. Leon of the U.S. District Court in Washington, D.C., said plaintiffs in the case had not shown that “irreparable harm” would result if the EAC’s action was not halted immediately.

The national chapter of the League of Women Voters, as well as its state chapters in Kansas, Alabama and Georgia, are challenging a decision last month by the EAC’s executive director, Brian Newby, to issue the new registration forms for those states, saying their proof of citizenship requirements conflict with the National Voter Registration Act, also known as the federal “motor voter” law.

The plaintiffs also asked the court for a temporary restraining order to block the use of the new forms, at least until the case is decided.

But in a four-page order released Wednesday, Judge Leon called such orders an “extraordinary remedy” that can only be used when the plaintiffs show clearly that they are entitled to the relief and failure to grant the order would result in irreparable harm.

He noted that the registration deadlines for the Georgia and Alabama primaries, as well as the Kansas Republican caucuses, have already passed, and it was not clear how the new requirement would affect the upcoming Kansas Democratic caucuses.

For the March 5 caucuses in Kansas, Republican voters must have been registered as Republicans by Feb. 4. The Democratic Party allows any voter to register as a Democrat on the day of the caucuses.

Currently in Kansas, voters can register using either a state or federal form. Until recently, though, only the state form asked them to show proof of U.S. citizenship. The federal form only asks applicants to attest, under penalty of perjury, that they are U.S. citizens.

In 2014, the EAC rejected requests by Kansas and Arizona to add a proof-of-citizenship question to the federal form, saying that doing so would “likely hinder eligible citizens from registering to vote in federal elections.”

Since then, Kansas Secretary of State Kris Kobach has said that voters using the federal form who do not provide proof of citizenship may only vote in federal elections. But a Shawnee County judge said in December that Kobach had no legal authority to make such a rule. That case is now under appeal.

On Jan. 29, the EAC’s new executive director, former Johnson County Election Commissioner Newby, acted unilaterally to grant requests from Kansas, Alabama and Georgia, even though the bipartisan commission had not authorized him to do so.

The U.S. Justice Department, siding with the plaintiffs, said earlier this week that it would not defend Newby’s action. But Kobach and the conservative Public Interest Legal Foundation were granted motions to intervene in support of Newby’s action.