ATHENS — Greece’s parliament on Thursday voted to investigate former Transport Minister Kostas Karamanlis from the ruling New Democracy party over his role in the country’s deadliest rail crash.

The vote took place in the early hours after a heated and often acrimonious parliamentary session.

The vote paves the way for a special parliamentary committee that will determine whether Karamanlis’ immunity should be waived so he can face criminal indictment for any potential liabilities that contributed to the head-on collision that killed 57 people, most of them students, in February 2023 in Tempi.

According to Greek law, only the country’s parliament can investigate allegations of misconduct against former ministers.

Karamanlis maintained his innocence during the debate but requested to be referred both to the committee and subsequently to the judicial authorities.

There were three separate proposals for investigating the rail disaster: New Democracy’s proposal targeted only Karamanlis and only on felony charges; the main opposition Pasok’s proposal named eight political figures; a third proposal, submitted by citizens including a victim’s relative and supported by smaller parties and independent lawmakers, targeted 11 political figures, including Prime Minister Kyriakos Mitsotakis himself, with charges of high treason.

The proposal by the ruling party, which holds the majority in government, eventually passed.

Opposition parties have accused the government of tabling its own proposal to avoid felony charges against government members.

Last year, the government dismissed a call from the European public prosecutor to take action regarding potential misappropriation committed by Karamanlis.