Türkiye’s oldest party, which brands itself as a social democrat, may be forced to pick a side or divide as it explores new alliances. The main opposition Republican People’s Party (CHP) founded by the republic’s founder and first President Mustafa Kemal Atatürk is criticized for supporting a mayor arrested over links to the terrorist group PKK.

The party’s leader Özgür Özel sought to rally mayors to protest the arrest, but most mayors did not comply with his call. Özel excused mayors, claiming they had public duties to attend, but political pundits say some mayors likely tried to distance themselves from the issue. Indeed, this was the case, at least for Burcu Köksal, CHP mayor for the western province of Afyonkarahisar, who defended her decision not to join the call in a tweet critical of the "fait accompli" decision and slammed the terrorist group.

The arrested mayor, Ahmet Özer, was a name affiliated with the Peoples’ Equality Party (DEM Party) before he was fielded as a candidate by CHP in the latest municipal elections. DEM is known for its intricate links to the terrorist group and three of its own mayors were also sacked earlier this week after they were convicted of membership of PKK.

Tanju Özcan, mayor of the northern province of Bolu, who is known for his feud with Özel’s predecessor Kemal Kılıçdaroğlu and his notorious far-right views, also shunned the meeting of mayors in support of Özer in Istanbul. Ali Haydar Fırat, a member of the party’s assembly, has called on the administration to suspend the party membership of two mayors, and some other members supported this call.

Meanwhile, Mansur Yavaş, CHP mayor for Ankara, who is known for his nationalist background, faced mounting criticism for not joining protesting mayors and protests against the sacking of DEM’s mayors. Yavaş reportedly assesses the current developments with his close circle, who presses him to leave the party amid rumors that he is being isolated within the party and his chances of being picked as CHP’s presidential candidate in the 2028 elections are slimmer now.

Elsewhere, Kemal Kılıçdaroğlu, who came at odds with Özel for the latter’s outreach to the government to normalize ties, is unifying his front within the CHP against the current administration. Kılıçdaroğlu’s supporters have tried to drum up more support for an intraparty election during a September convention but failed. This time, they seek to collect signatures from some 50 lawmakers for a petition to hold another election. The said lawmakers complain of isolation within the party. The CHP’s strictly secular and, at times, left-wing rhetoric gradually changed in the past two decades, where it was repeatedly defeated by the ruling Justice and Development Party (AK Party) and "old school" CHP members more adherent to the founding principles of the party were alienated either by Kılıçdaroğlu or Özel, though both men apparently had differing political views.