The first round of a vote that could see the immunity of more than 130 members of the Turkish legislature lifted, a move the country's pro-Kurdish party says is aimed at its deputies, is set to go ahead on Tuesday.
Parliamentarians facing potential prosecution come from all four parties in parliament, but the pro-Kurdish Peoples' Democratic Party (HDP) would be most disproportionately affected, with about 50 of its 59 members in parliament at risk.
Backers of the move say it is intended to remove immunity from those who have existing police dossiers.
Discussions about the move - which is being organized by the ruling Justice and Development Party (AKP) - have led to fistfights in the parliament's committees. Debate in the main plenary is also likely to be heated.
"What this motion seeks to destroy is the HDP opposition in the parliament," Figen Yuksekdag and Selahattin Demirtas, the co-leaders of the party, wrote in a letter to European parliamentarians.
Both leaders face having their immunity lifted and accuse the government of a "totalitarian attack," warning that the moves against the Kurdish minority could lead to even more violence in the country.
Conflict between the state and the armed Kurdistan Workers' Party flared up again in 2015 after a two-year ceasefire collapsed. Many hundreds have since died, with the death toll rising daily, including civilians, members of the security forces and civilians.
"Silencing democratically elected opposition MPs for their political statements is the obstruction of parliament and against democratic principles," a group of European Parliament members from several parties said in an open letter.
"Excluding democratically elected members of the parliament is not the way to deal with the Kurdish problem."
The government says the proposed bill would only target those who have police proceedings ongoing against them.
President Recep Tayyip Erdogan, a founder of the AKP - which has a majority of 317 seats in 550 member parliament - has repeatedly called for the immunity of HDP deputies to be lifted, accusing them of cooperating with the banned PKK.
"Neither we nor this nation can be expected to make an effort to tolerate deputies who do nothing but act as a mouthpiece for the separatist terrorist organization," he said in February, according to the state-run Anadolu news agency.
The AKP will need the support of other groups in parliament to push through the removal of immunity, a constitutional issue, without having to go to a referendum.
Turkish media has said the far right Nationalist Movement Party (MHP), which is staunchly anti-Kurd, will likely come on board. The centre-left People's Republican PartY (CHP) could see some members vote in favour, though the party's chief has an existing dossier.
The final vote is not expected until Friday at the earliest, but could be pushed back as far as May 24.