The charges come as Donald Trump himself faces a court hearing on criminal charges for 2020 election interference.
The announcement came just hours before the former president was due to appear in a Washington, DC, court on criminal charges that he conspired to cling to power.
Stefanie Lambert Junttila, who along with other Trump allies tried to reverse Trump’s defeat to Democratic President Joe Biden in Michigan, was charged with accessing, tampering with and undue possession of voting machines in the state, according to court records.
Lambert was the third person charged in Michigan this week after a special prosecutor in that state reviewed allegations that Trump allies illegally accessed voting machines after the 2020 election.
Two other Michigan Republicans — former Michigan attorney general candidate Matt DePerno and Daire Rendon, a former state representative — made their initial court appearances on Tuesday in connection with the case.
All three were named last year by Michigan’s Attorney General Dana Nessel, in an investigation of a scheme to access voting tabulators. Nessel, a Democrat, defeated Trump-endorsed DePerno in her re-election bid last year.
In a call with reporters last week, Junttila called the case a “malicious prosecution”.
The Michigan case is a separate prosecution from Trump’s latest indictment.
Trump was appearing in court on Thursday accused of leading a conspiracy built on lies to overturn the 2020 presidential election, culminating in the January 6, 2021 attack on the US Capitol.
In a 45-page indictment on Tuesday, special counsel Jack Smith accused Trump and some allies of promoting false claims the election was rigged, pressuring state and federal officials to alter the results and assembling fake slates of electors to try to wrest electoral votes from Biden.
It is the third time Trump has been indicted this year.
He has pleaded not guilty to federal charges that he retained classified documents after leaving office and New York state charges that he falsified documents in connection with hush-money payments to a pornographic movie star.
Trump may soon face more charges in Georgia, where a state prosecutor is investigating his attempts to overturn the election there.