The Turkish parliament on Tuesday begins debating a hugely controversial bill that would strip dozens of deputies of their parliamentary immunity and which pro-Kurdish lawmakers say is directly aimed at driving them out of the legislature.
The bill has already led to unprecedented scenes at the committee stage with deputies exchanging angry blows with their fists and even feet rather than discussing the document.
The day's parliamentary session began in the afternoon with the debates on the bill, which could prove fiery and go late into the night, set to get under way later.
A final vote is expected on Friday.
Under current Turkish law, MPs in parliament have the right to full immunity from prosecution. If passed, the bill would lift the immunity of 130 deputies from all parties whose dossiers have been sent to the parliament speaker.
But the pro-Kurdish Peoples' Democratic Party (HDP) says the bill is essentially a drive to expel its MPs from parliament.
HDP MPs are particularly vulnerable to prosecution on allegations of links or even verbal support for the outlawed Kurdistan Workers Party (PKK), which is fighting a renewed insurgency against the Turkish state.
"What this motion seeks to destroy is the HDP in parliament," party co-leaders Selahattin Demirtas and Figen Yuksekdag, both of whom could face prosecution, said in a letter to European MPs.
Should a number of HDP deputies leave parliament, it would ease the path for President Recep Tayyip Erdogan to realise his dream of changing the constitution to create a presidential system in Turkey.
The HDP said the bill could lead to the prosecution of 50 HDP MPs out of its total contingent of 59.
"If successful, this coup would be a most crucial step for Erdogan to replace Turkey's parliamentary democracy... with an absolutist presidential system," the HDP's co-leaders said.
Should the bill become law, it raises the prospect that the likes of Demirtas and Yuksekdag -- already the target of criminal investigations -- could go on trial on charges of making "terrorist propaganda" for the PKK and even face time in jail.
The ruling Justice and Development Party (AKP) needs to win 367 votes in the 550 seat parliament -- a two-thirds majority -- to push the legislation through directly.
A three-fifths majority -- 330 votes -- is enough to call a referendum on the issue.
The AKP has 317 seats in parliament and is hoping to enjoy support for the motion from the Nationalist Movement Party (MHP), which despises the HDP and has 40 seats.
But the MHP is itself in turmoil after its poor performance in November elections, with several figures trying to challenge longtime chief Devlet Bahceli, and the AKP may also need support from the main opposition Republican People's Party (CHP).
Bulent Turan, the head of the AKP's faction in parliament, said he would prefer that parliament resolved the issue itself but emphasised the party had "no fear" of a referendum should the need arise.
He denied that the motion was specifically aimed at the HDP.
"If some people within the AKP did something wrong then they will be judged," he said.
The removal of parliamentary immunity has a precedent -- in 1994 four deputies from the now defunct predecessor of the HDP the Democratic Party, including Sakharov Prize winner Leyla Zana, were jailed on charges of membership of the PKK immediately after having their immunity removed.