By KEMAL KILICDAROGLUJULY 7, 2017

GEBZE, TURKEY — On June 15, I began walking from Ankara to Istanbul on a 280-mile march for democracy, justice and freedom from fear and authoritarian rule in Turkey. I am the leader of the Republican People’s Party, or C.H.P., the main opposition party in the Turkish Parliament. I set out with thousands of supporters from Ankara.

As we walked through punishingly hot afternoons and plodded on through rain for the past three weeks, tens of thousands of Turkish citizens of varying political persuasions representing the diversity of our country joined us. We did not carry the signs of our political party but a simple placard that read: Justice.

The day before I began the march, Enis Berberoglu, a member of Parliament from my party, who edited Hurriyet, the largest Turkish newspaper, before running for office, was arrested. The official case alleges that he leaked a video about the Turkish intelligence supplying arms to rebels in Syria to an opposition newspaper.

Mr. Berberoglu’s arrest was the last straw in a series of antidemocratic moves by President Recep Tayyip Erdogan’s government targeting tens of thousands of Turkish citizens — politicians, journalists, academics, activists or ordinary citizens.

So they are asking, “Can you look for justice on the streets?” It is not a choice but an obligation. If democracy and rule of law are suspended, if people are afraid to freely express their views, if legislators are in prison rather than in the Parliament, if the courts are incapable of serving justice, we stand up and call for justice with our words, with our bodies on the streets.

On July 15, 2016, Turkish military officers affiliated with the network of Fethullah Gulen, former ally of the ruling Justice and Development Party, attempted a failed but bloody coup against the Turkish government. The coup plotters murdered 249 Turkish citizens, injured thousands more, and bombed and destroyed parts of the Turkish Parliament.

My party and other opposition parties came together with Mr. Erdogan’s Justice and Development Party (A.K.P.), and we called upon the Turkish people to defend parliamentary democracy. Our people came out on the streets and fought the putschists, rebutted the abominable coup attempt.

The putschists and their supporters, including some state officials and civilians, had to be tried and prosecuted for their crimes. We supported the prosecution of the putschists and the legal measures the government had to take to prevent such attempts in the future.

We expected the letter and the spirit of the law to be followed. Unfortunately, that was not to be the case. Five days after the failed coup attempt, on July 20, 2016, President Erdogan declared a state of emergency. He de facto bypassed the Parliament and started ruling by decrees. It was the second coup, a civilian coup by Mr. Erdogan.

In the following year, more than 50,000 people have been jailed and over 150,000 people have been fired from their jobs with midnight decrees. Teachers, judges, prosecutors, academics, civil servants and journalists have been taken from their homes after dawn raids by the counterterror police. They have been in prison for months with no indictment in sight, and we don’t know if they have any links with the coup plotters.

Twelve members of the Turkish Parliament and more than 150 journalists have been imprisoned and charged with supporting terror because of their speeches, writings or tweets. Turkey has been wrapped in a cloak of fear and anxiety.

Nine months after the coup, on April 16 of this year, Mr. Erdogan had a referendum to make a series of constitutional amendments. It granted him increased powers allowing him to retake his position as the head of the A.K.P.; scrap the position of the prime minister; appoint judges, and ministers; prepare the budget and enact laws by decree; and dismiss the Parliament, among other things.

Mr. Erdogan didn’t win a fair vote. The government misused administrative resources for the pro-referendum campaign in violation of laws and international commitments. The media granted little space to the opposition campaign against the referendum. The arrests of journalists and the closure of media houses led to self-censorship.

An opposition party’s key political figures were kept in prison and prevented from campaigning. Upon A.K.P.’s request, Turkey’s Supreme Board of Elections changed vote-counting procedures and removed an important safeguard. Yet half of Turkey voted against the referendum and increased powers for Mr. Erdogan.

The changes brought about by the referendum hollowed out the principle of separation of powers in our already problematic democracy and further eroded the rule of law. Power is concentrated in Mr. Erdogan’s hands. Turkey is ruled by one man.

As we approach the first anniversary of the coup, tens of thousands of people who were arrested in the purges are yet to stand trial and get a fair chance to defend themselves. Judicial independence has been eliminated. The judges and prosecutors who take decisions against the government’s can be easily removed from their offices and arrested.

So we walk for all our fellow citizens wishing to live in peace and harmony in Turkey: for believers and nonbelievers; for Turks and Kurds; for Alevis and Sunnis. We walk for a Turkey in which beliefs, ethnicity and lifestyle do not became a reason for discrimination and punishment. We walk for a Turkey in which heads are held high and minds are without fear.

Mr. Erdogan and the government described our march as “a march for terrorists and for their supporters.” He couldn’t be more wrong. I walked with a broad range of Turkish people: wives of imprisoned journalists who want freedom for everyone who has been arrested for his views; families of terror victims who want enduring peace; a father whose son has been wrongly accused of involvement in the coup attempt; farmers who can’t get enough returns for their toil; young people who are worried about their future; and women who suffered domestic violence and seek equal rights.

Along the way, people welcomed us by car horns, or simply waved. Sometimes they joined our chants: Adalet! Justice!

On July 9, I will reach İstanbul and complete the march for justice with a big rally. We want the state of emergency to be lifted and democracy restored. We want the restoration of an independent judiciary and quick, fair trials for the detainees and prosecution of the putschists. Legal mechanism shall be set up to address the cases of tens of thousands of sacked public servants. Nobody should be jailed because of his views, speeches, writings or drawings. All imprisoned journalists and academics should be freed immediately.

Each mile of this long march for justice has buoyed my hopes. I am certain that the people of Turkey will reinstate democracy and justice will return to my country.

Kemal Kilicdaroglu is the Chairman of Republican People’s Party (C.H.P.), the leading opposition party of Turkey.