President Trump suffered multiple legal setbacks in three key swing states on Friday, choking off many of his last-ditch efforts to use the courts to delay or block President-elect Joseph R. Biden Jr.’s victory.
In quick succession, Mr. Trump was handed defeats in Pennsylvania, Arizona and Michigan, where a state judge in Detroit rejected an unusual Republican attempt to halt the certification of the vote in Wayne County pending an audit of the count.
The legal losses came as Mr. Biden was declared the victor in Georgia and a day after an agency in the president’s own Department of Homeland Security flatly contradicted him by declaring that the election “was the most secure in American history” and that “there is no evidence” any voting systems malfunctioned.
On Friday, 16 federal prosecutors who had been assigned to monitor the election also directly debunked claims of widespread fraud, saying in a letter to Attorney General William P. Barr that there was no evidence of substantial irregularities.
In his first public remarks of the week, Mr. Trump ignored the developments during an appearance in the Rose Garden. But he showed a momentary crack in his previously relentless insistence that he would eventually be proclaimed the winner of the campaign, saying at one point, “Whatever happens in the future, who knows, which administration, I guess time will tell.”
Mr. Trump’s bad day at the bar began at dawn when news emerged that lawyers from the Ohio-based law firm Porter Wright Morris & Arthur had abruptly withdrawn from a federal lawsuit they had filed only days earlier on his behalf in Pennsylvania. The firm’s withdrawal followed internal tensions at the firm about its work for Mr. Trump and concerns by some lawyers that Porter Wright was being used to undercut the integrity of the electoral process.
Then, shortly after noon, a lawyer for the Trump campaign effectively dropped its so-called Sharpiegate lawsuit in Arizona. That lawsuit had claimed that some ballots cast for Mr. Trump were invalidated after voters in Maricopa County had used Sharpie pens, causing “ink bleeds.” The lawyer, Kory Langhofer, acknowledged that not enough presidential votes were at stake in the case to affect the outcome of the race.
The lawsuit, which stemmed from a viral rumor that falsely claimed Arizona’s voting machines were incapable of tabulating ballots filled out with Sharpies, was already on the rocks. At a hearing on Thursday, Mr. Langhofer told the court that the county’s vote count had been affected merely by “good-faith errors,” not by fraud, as Mr. Trump has been claiming for days.
“We are not saying anyone is trying to steal the election,” Mr. Langhofer said.
With victories in Arizona and Georgia, Mr. Biden has matched the 306 electoral votes that Mr. Trump racked up four years ago. Mr. Biden was declared the winner of Arizona’s 11 electoral votes on Thursday night after he finished more than 11,000 votes ahead of Mr. Trump. At the court hearing earlier that day, a Maricopa County elections official testified that only 191 presidential votes in the county might have been affected by Mr. Langhofer’s suit.
Around 2 p.m. Friday, the state court judge in Michigan, Timothy M. Kenny, dealt Mr. Trump another blow by denying an emergency motion filed by two Republican poll workers who had asked him to halt the certification of the vote in Wayne County — home to Detroit — pending an audit of the count. States have to certify the results of the election — confirming that the vote tabulation was accurate — in order to apportion their Electoral College votes.
The ruling by Judge Kenny meant that the formal completion of the vote in Wayne County — and the broader vote in Michigan — could continue on pace. Some legal scholars have suggested that delaying certification of the vote in key states is part of a last-ditch strategy by the Trump campaign to throw the election to Republican-led state legislatures.
At a hearing this week in Detroit, lawyers for the city had asked Judge Kenny not to delay certification out of concern about this gambit. In his ruling, the judge noted that the audit requested by the two Republican plaintiffs, Cheryl Costantino and Edward McCall, would have been “unwieldy” and forced the rest of Michigan to wait.
“It would be an unprecedented exercise of judicial activism for this court to stop the certification process,” Judge Kenny added.
In a lawsuit filed last week, Ms. Costantino and Mr. McCall had made wide-ranging claims of irregularities during the vote count at Detroit’s TCF Convention Center.
They charged that some poll workers in the heavily Democratic city were coaching voters to cast their ballots for Mr. Biden, that some Republican poll challengers were not given adequate access to monitor the vote count, and that loads of ballots were improperly brought into the convention center in the middle of the night.
Lawyers for Detroit and for the Michigan Democratic Party had argued in court papers that about 100 Republican poll challengers had in fact been let into the convention center, but that some were not allowed to return after leaving once the room filled up.
Judge Kenny wrote that while he took some of these accusations seriously, some were too general to be proved and others were “rife with speculation and guesswork.”
He dismissed an affidavit by one Republican poll observer charging that computers at the convention center had been improperly connected to the internet, noting that the observer’s credibility was suspect: Before the election, the observer had posted on Facebook that the Democrats were using the coronavirus crisis as “a cover for Election Day fraud.”
In between the events in Arizona and Michigan, another court, the United States Court of Appeals for the Third Circuit, in Philadelphia, handed the president another defeat.
The court upheld Pennsylvania’s three-day extension for the deadline to accept mail-in ballots, against which the Trump campaign has vociferously fought. The Pennsylvania Supreme Court had already issued a similar decision, and the U.S. Supreme Court refused to accept Mr. Trump’s attempt to challenge it.
As the president was speaking in the Rose Garden, Marc E. Elias, a lawyer who has handled several election cases on behalf of the Democrats, wrote on Twitter: “Another Friday afternoon with more good news coming from the courts.”
That turned out to be two more victories in Pennsylvania.
In one, a Montgomery County Common Pleas Court denied the Trump campaign’s request to invalidate a batch of mail-in ballots. In the other, a Philadelphia County Common Pleas Court rejected the campaign’s appeal seeking to invalidate five more batches of mail-in ballots.
The total number of ballots at stake in the two decisions: 8,927.
Mr. Trump was not ready to give up. He posted on Twitter on Friday evening that he would win in Pennsylvania, making a baseless assertion about vote counting in Philadelphia and Pittsburgh.
With the legal fight not going well, the president put his personal lawyer, Rudolph W. Giuliani, in charge of his campaign lawsuits related to the outcome of the election, as well as all public communications related to them, four people familiar with the move said.
Mr. Trump has been trying every possible option to change the outcome and has been trying to get what he sees as “fighters” making his case, often conflating a media strategy with a legal one.
But the involvement of Mr. Giuliani, who held a widely mocked news conference last weekend in front of a landscaping company in Philadelphia in which he claimed widespread fraud, has vexed people on the campaign and in the White House.
The Trump campaign and its proxies still have some cases working their ways through the courts, including one in Federal District Court in Grand Rapids, Mich., that closely mirrors the Michigan state case that Judge Kenny ended on Friday.
A lawsuit seeking to delay certification of the vote in several counties in Wisconsin was filed on Thursday in Federal District Court in Green Bay. On Tuesday, a federal judge in Williamsport, Pa., will hear arguments in a lawsuit that seeks to halt the certification of the vote in several counties in that state.
Maggie Haberman contributed reporting.