's parliament on Friday approved a bill to amend the constitution to strip lawmakers of immunity, a move that paves the way for trials of several pro-Kurdish and other legislators.
A total of 376 deputies in the 550-seat assembly in Ankara
voted in favor of the government-backed bill, which was enough to avoid a referendum. It now needs to be ratified by the president.
The amendment was proposed by the ruling Justice and Development Party after the president accused the pro-Kurdish party, People's Democratic Party, HDP, of being an arm of outlawed Kurdish rebels and repeatedly called for their prosecution on terror related charges. It puts 138 lawmakers, the vast majority of them from two opposition parties, at risk of prosecution.
The result of the vote was criticized by officials in the European Union
and condemned by Turkish opposition lawmakers, who said they would fight against it.
Speaking in the Black Sea town of Rize moments ahead of the final round of voting, Turkish President Recep Tayyip Erdogan expressed hope the bill would be adopted, saying "my people don't want to see criminal deputies in parliament."
The decision coincides with a wave of violence in Turkey's southeast following the collapse of a more than two-year peace process between the state and the outlawed Kurdistan Worker's Party, or PKK.
The HDP, which backs Kurdish and other minority rights, denies accusations that it is the political arm of the PKK, considered a terrorist group by Ankara and its allies. The party has urged the government to end security operations in the southeast and to resume peace efforts.
Turkey has a history of excluding Kurds from politics and critics see the bill as an effort to wipe out the pro-Kurdish party at a time when Erdogan is trying to push forward other controversial reforms, including a constitutional amendment to transform Turkey into a presidential system.
Out of 667 legal files, 405 are against the HDP and 102 concern members of the main opposition Republican People's Party (CHP), according to a Turkish official, who spoke on condition of anonymity because he is not authorized to speak publicly on the issue.
The parliamentarians at risk of prosecution fall roughly into three categories: those who like HDP members are accused of supporting the PKK, those who are accused of insulting the president, and those under investigation for corruption or other criminal offenses.
Murat Somer, politics professor at Istanbul's Koc University, said the legal proceedings risk paralyzing parliament and weakening government oversight. The legality and constitutionality of the amendment is also likely to come under question.
"Parliament is one important platform where the opposition can voice its criticism and represent its interest but now the parliament itself will be weakened," he said. "It will create a long series of legal questions and complexities."
Turkey is undergoing a period of political transition as Prime Minister Ahmet Davutoglu has announced he will be stepping down. On Sunday the ruling party is due to confirm an ally of the president, Binali Yildirim, as the next premier and party chairman. Many see the shake-up as one in a series of measures designed to concentrate power in the office of the presidency.
Speaking after the vote, HDP co-chair Selahattin Demirtas struck a defiant tone saying a request would be presented to the Constitutional Court to abolish the amendment.
"No one from our party, including me, will go to the court will-nilly as if nothing has happened," he said. "Everyone should know this. The fighting has just started."
The result of the vote caused alarm in the EU, which has been working closely with Turkey to address the migrant crisis despite a series of controversies relating to human rights and press freedom that have put pressure on their relationship.
EU foreign policy chief Federica Mogherini and Johannes Hahn, the bloc's top official for enlargement, issued a joint statement describing the decision as a "matter of serious concern."
"A restrictive interpretation of the legal framework and the Constitution in particular continue to pose a risk to the freedom of expression of Members of Parliament in Turkey," they added.
German government spokesman Steffen Seibert also expressed concern "about the increasing polarization of the domestic debate in Turkey" and said it would be a topic of discussion in an upcoming meeting between German Chancellor Angela Merkel and her Turkish counterpart.
The NATO member is also part of the U.S.
-led alliance against the Islamic State group.