Tánaiste Joan Burton is to be a key witness when socialist TD Paul Murphy and more than 20 other water protesters face trial.
The Director of Public Prosecutions has decided to bring charges against 23 people who were involved in a protest last November that saw Ms Burton trapped in a car for nearly two hours. They will face a variety of charges including false imprisonment and criminal damage.
The Irish Independent understands that Mr Murphy is to be among those brought to court within the next 10 days.
Two Anti-Austerity Alliance councillors, Kieran Murphy and Mick Murphy, will also face charges.
A source close to Ms Burton said the DPP's decision had "come out of the blue". The Labour Party leader now faces having to give evidence in court early next year while fighting the general election.
The protesters are to be brought before the Circuit Court, where sentences can be much more severe than at district level.
Paul Murphy, a TD for Dublin South West, described the developments as "a serious attack on civil liberties and the right to protest. I don't believe that I or others committed false imprisonment. I reject that in its entirety."
Ms Burton has previously said that Paul Murphy "was ecstatic - grinning from ear to ear, like a child" while she was trapped in the car.