As a teenager, Elif Bulut’s neighbours advised her family to keep quiet about her father’s Kurdish roots because “they disliked Kurds” in the conservative Black Sea town to which they had moved.

The warning was Bulut’s first realisation that her background set her apart in Turkey. “I wasn’t born into politics, but if you have an ethnic identity, if you’re a woman with dissenting views, you are thrust into politics,” said Bulut, 44, who is now the chair of the Istanbul branch of the People’s Democratic party (HDP).

Most of the 5.9m people who voted for the left-leaning HDP, Turkey’s second-biggest opposition party, in a 2018 general election are Kurdish. The party campaigns for a negotiated settlement in a 36-year conflict between the state and the armed Kurdistan Workers’ party (PKK), which has been designated a terror group by the EU and US.

Turkey’s president, Recep Tayyip Erdogan, has accused the HDP of being the PKK’s political wing and said earlier this year there was no room in Turkish politics for a party that did not “wholeheartedly condemn” the militants. The HDP denies links with the PKK, which wants greater political autonomy for Kurds in Turkey.

The government’s campaign against the HDP has been stepped up in recent weeks, with the country’s top prosecutor seeking to outlaw the party and several of its senior politicians facing possible life sentences if convicted in a separate trial. The crackdown is testing the commitment of the party’s grassroots activists.

The HDP has thousands of volunteers in Istanbul, a city with about 2m Kurdish residents.

The prosecutions cast “great black clouds over our party by criminalising it to try to weaken our bond with voters”, said Bulut. But, she added: “Our voters are well acquainted with pressure and will not abandon us.”

The legal blitz is the climax of a years-long campaign by the Turkish government, during which almost all of the HDP’s mayors have been expelled from office across mainly Kurdish southeastern provinces, several lawmakers were stripped of their seats in parliament and thousands of party activists have been jailed. Pro-Kurdish newspapers have been banned and Kurdish-language schools and theatres shut.

Both the EU and US have criticised Ankara’s move to close the party and the Constitutional Court has asked the prosecutor to remedy deficiencies in the indictment, which has delayed the start of the trial.

Another court began trying 108 senior HDP politicians last month, including its jailed former leader Selahattin Demirtas, for allegedly inciting deadly riots in Turkey in 2014 to protest against Isis’s siege of Kobani, a Kurdish-run town in northern Syria, that year. HDP officials believe the case is intended to lay the legal groundwork for a ban.

“People took to the streets in a cry for help when Kurds faced annihilation in Kobani,” said Zubeyde Ince, 55, a retired teacher who volunteers in the HDP’s voter outreach programme. Opening a court case more than six years later was proof that “Turkey is hostile to Kurds”.

Ince, who has backed the Kurdish political movement for three decades, said voters’ support for the HDP remained strong. “The Kurdish people and our cause won’t disappear if they ban the HDP. Our party isn’t a sign they can take down. We are the party.”

The HDP is the latest incarnation of a movement that began in 1990 to push for greater cultural and political rights for Turkey’s 14m Kurds. Five predecessors were banned, the last in 2009, and the HDP has vowed to re-form under the banner of a sister party or through another alliance if it, too, is outlawed.

Erdogan, whose stance towards the HDP hardened after the 2015 collapse of a peace process with the PKK, “thrives off crisis and enmity by disparaging the HDP”, said Bulut.

Polls show the HDP’s support has declined since the 2018 election, but at a slower rate than for Erdogan’s Justice and Development party (AKP), which has historically attracted the second-highest number of Kurdish votes.

Tightening the screws on the HDP helps brandish the AKP’s nationalist credentials and stimulate its base, said political scientist Sezin Ozey. “The scapegoating produces the polarisation that distracts from other problems during the coronavirus pandemic,” she said. “Demonising the HDP also helps neuter the rest of the opposition.”

The prosecutor in the case to close the HDP is also seeking a ban from political life for nearly 700 HDP members, including 24-year-old sociology major Yagmur Yurtsever, who was drawn to the party when she began university because of its pledge to promote gender equality in its ranks.

Since then, Yurtsever has been detained by police four times over allegations ranging from violating protest bans to membership of a terrorist organisation. “Because I belong to the HDP, the state accuses me of being PKK, and because I’m accused of being PKK, they say that’s grounds to close the HDP. It’s a vicious cycle,” she said.

“The state pushes people to war by shutting the space for politics. That frightens me, but what gives me comfort is that the HDP’s commitment to peaceful struggle is resolute,” she added. “War has failed to bring a new paradigm, but I genuinely believe democratic politics will.”