The investigation relates to three graphic images of Daesh executions that she posted on Twitter in December 2015, including the beheading of American journalist James Foley. Le Pen condemned an earlier stage of the investigation as "political interference".
Marine Le Pen is facing charges of reporting "violent messages that incite terrorism or pornography or seriously harm human dignity" and that could be viewed by a minor. The crime is punishable by up to three years in prison and a fine of 75,000 euros ($91,000).
Bonsoir Marine: @MLP_officiel en levant son immunité parlementaire concernant le RT de photos de #Daesh J'ai trouvé ceci sur Internet comme toi Marine un personne qui montre comme toi les atrocités #SoutienMarine #FN pic.twitter.com/y856QnNQH7— chti@laurent🐝 (@MARINEPouvoirFR) November 10, 2017
"I am being charged for having condemned the horrors of Daesh. In other countries, this would have earned me a medal," Le Pen told AFP.
Le Pen's post which was later deleted, said "Daesh in THIS!" showing three pictures, one of which was of the decapitated body of Daesh victim, James Foley. The image provoked an outcry on social media, as well as condemnation from Foley's family, leading to an investigation launched by the French authorities in 2015.
Lately, she wrote on Twitter, "In Syria, civilians are being used as human shields by jihadists, as the latter had done in Aleppo. Let's not be naive!"
The National Front leader, who came second in the latest presidential election, has been a vocal supporter of tougher security measures in the wake of multiple terrorist attacks and called for a decisive fight against Daesh.