Rudy Giuliani, a former lawyer for Donald Trump, is among 18 people charged in Arizona with illegally seeking to claim the state's 2020 electoral votes for the then-US president, in an indictment that names Trump as an unindicted co-conspirator.
The indictment, reached on Tuesday and unsealed on Wednesday, stems from the attempt by Trump and his allies to pressure election officials in several states to overturn the presidential election won by Joe Biden, efforts for which Trump has been indicted in Georgia and in federal court.
The court papers list "a former US president", referring to Trump, as an unindicted co-conspirator.
The indictment in Maricopa County Superior Court names 11 defendants and redacts the names of seven others, on charges including fraud, forgery and conspiracy.
Arizona Attorney General Kris Mayes said those names would be made public after all the defendants had been served with the indictment.
Giuliani was among those whose names are redacted, a spokesperson for him, Ted Goodman, confirmed, criticising the prosecution of the former New York mayor as political.
Another defendant whose name was redacted is described in the indictment as chief of staff in 2020, the position Mark Meadows held in the Trump White House at that time.
Representatives for Meadows did not immediately respond to a request for comment.
Trump, Giuliani and Meadows are co-defendants in the Georgia case, where they are charged with a racketeering conspiracy to overturn Biden's victory in that state. They have pleaded not guilty there.
Trump has also pleaded not guilty in the federal election-subversion case in Washington.
Trump, a Republican, says the cases are a political "witch hunt" to prevent him defeating Democrat Biden in the 2024 presidential rematch.
Another defendant whose name is redacted is Trump lawyer Christina Bobb, Trump spokesman Steven Cheung confirmed, calling the Arizona indictment "another example of Democrats' weaponisation of the legal system".
Giuliani's spokesman also called the Arizona indictment an example of "the continued weaponisation of our justice system", saying it "should concern every American as it does permanent, irrevocable harm to the country".
The indictment alleges the defendants pressured the Maricopa Board of Supervisors, the Arizona Legislature and then-governor Doug Ducey to change the election results.
US presidents are chosen by electors from each state, who cast votes in the electoral college.
To win the presidency a candidate needs 270 electoral votes - a majority of total 538.
Arizona has 11 electoral votes, and the 11 defendants would correspond to those people who purported to be electors for Trump.
Arizona is one of seven states where Biden won but Trump allies sought to award the electoral votes to Trump.
Many of the races were close, with Arizona decided by fewer than 10,000 votes or 0.3 per cent of ballots cast.
Arizona is the fourth US state where participants in the elector scheme have faced criminal charges.
Three people who held themselves out as Trump electors in Georgia were charged alongside Trump in the racketeering case brought by Fulton County District Attorney Fani Willis.
Sixteen people who falsely claimed to be legitimate Trump electors in Michigan were indicted by state Attorney-General Dana Nessel.
Authorities in Nevada charged six people, including the state Republican chair, with taking part in the scheme.
The so-called fake elector plan also plays a prominent role in the federal case against Trump brought by Special Counsel Jack Smith, accusing the former president of a multi-part scheme to overturn the results of the 2020 election.
Trump will press his claim that he should be immune from those charges at the US Supreme Court on Thursday.
