The judge scheduled testimony Thursday from a former state GOP official-turned-Trump campaign official, Jesse Law, about whether training for poll-watchers was "confusing or misleading" about rules they need to follow if they challenge a voter at the polls.
Boulware told attorneys for the Democratic and Republican parties that he wasn't convinced there was a firm link between the Trump and a named defendant, party official Roger Stone Jr., or between the campaign and the state party.
"We haven't established that Mr. Trump and Mr. Stone have sent people to the polls here in Nevada ... for the purpose of voter intimidation and coercion," the judge said.
But he said that if he finds evidence of intentional omissions in training he might order email reminders to be issued to poll-watchers.
Boulware declared also that he intends to rule by the weekend.
"If it's not done before then, it's not going to happen," he said.
The hearing in Nevada was the first after four similar lawsuits were filed in recent days in four presidential battleground states — also including Arizona, Ohio and Pennsylvania.
A hearing in the Arizona case was scheduled Thursday before a federal judge in Phoenix.
In Nevada, Democrats accuse the Trump campaign, Stone and his group called "Stop the Steal" of a "coordinated campaign of vigilante voter intimidation."
"Stone and Stop the Steal Inc. are actively recruiting Trump supporters for 'exit polling' specifically targeting nine Democratic-leaning cities with large minority populations, including Las Vegas," attorney Bradley Schrager said in a request for a temporary restraining order.
However, attorney Bruce Spiva, a Washington, D.C.-based lawyer for a firm that does work for the Democratic National Committee, conceded in court that the plaintiffs didn't know if Stone had been served with the Nevada lawsuit.
Stone didn't immediately respond to emails Wednesday about the case. He said in a statement after the Nevada lawsuit was filed on Sunday that his group conducts neutral interviews to detect any deviance between voting machine results and exit poll results.
"We seek only to determine if the election is honestly and fairly conducted and to provide ... an evidentiary basis for a challenge to the election if that is not the case," the statement said.
In court filings, the Nevada State Democratic Party declares the suggestion of widespread voter fraud in modern American politics "itself a fraud."
The lawsuit cites provisions of the Ku Klux Klan Act of 1871 and the Voting Rights Act of 1965 that prohibit intimidating or threatening voters.
The lawsuit alleges that Trump supporters have yelled at voters outside Las Vegas-area polling places, and points to instances of what it calls "bogus claims of voter fraud" by Trump in recent weeks including calls to supporters in rural Pennsylvania and Ohio to "watch" polling in urban areas so the election can't be stolen from him.
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