Two years ago, when I started investigating the sprawling prosecution of Turkey’s military and political leaders—known as the Ergenekon case—someone pointed me to Emin Şirin. At the time, more than seven hundred people from across Turkish society, from military officers to academics, journalists, and aid workers, had been charged with, among other things, attempting to overthrow the government of Prime Minister Recep Tayyip Erdoğan. Şirin’s story, I was told, was emblematic of the Ergenekon prosecutions, in that it relied on obviously trumped-up evidence.

Şirin, who speaks perfect English and has travelled in the United States, was once one of Erdoğan’s closest confidants. In 2001, he helped found Erdoğan’s political party, known by its Turkish initials, A.K., and was elected to parliament in 2002, when the Party won a landslide victory. Shortly after Erdoğan became Prime Minister, in 2003, Şirin broke with him, accusing Erdoğan of running the A.K. Party in a dictatorial fashion. Şirin completed a lonely term in parliament and left office in 2007. A month later, prosecutors charged him with membership in Ergenekon—allegedly a secret network of secular-minded Turks bent on overthrowing Erdoğan’s Islamist-leaning government.

Sure enough, when I looked at Şirin’s court file, I was astounded. The evidence against Şirin was not merely thin; it was preposterous, as though it had been assembled by a group of schoolchildren—or by a prosecutor who never imagined that an independent observer would examine it. The central piece of evidence against Şirin was a fifteen-page transcript of wiretapped telephone conversations that Şirin had allegedly made to other Ergenekon members. Yet nothing in the transcript appeared remotely criminal in nature; many of the calls were to Şirin’s girlfriend. And—here’s the showstopper—all of the recorded calls were made after his arrest. When I asked a senior Turkish prosecutor about it for my story, he told me, “It’s not one of the strongest cases.”

Last week, a Turkish court sentenced Şirin to seven and a half years in prison. Şirin was convicted along with two hundred and fifty-seven other defendants, including some twenty journalists and three members of parliament. Nineteen of the convicted, who include Ilker Basbug, the former chief of staff of the Turkish military, were sentenced to life in prison; several others received sentences of ninety-nine years or more. Şirin says that he plans to appeal his conviction. But if the Turkish appellate judges even remotely resemble their brethren in the lower courts—and there is no reason to think that they don’t—Şirin and the others don’t stand a chance.

The sentences handed down last week bring the number of imprisoned Turkish leaders to five hundred and seventy-two. Hundreds of others are awaiting trial, many of them in prison. No one seems to know where the Ergenekon case begins or ends.

Şirin’s case wasn’t the first to rely on questionable evidence. One of the other alleged military-coup plots I reported on was known as Sledgehammer, and was said to date to Erdoğan’s early days as Prime Minister. As in the Ergenekon case, the Sledgehammer prosecution was riddled with fabrications and exaggerations: the conspiracy supposedly came together in 2003, yet much of the evidence assembled against the generals was dated after that. For instance, one section of the so-called Sledgehammer plot lists a number of hospitals to be seized once the coup got under way, including an institution in Istanbul called Medical Park Sultangazi. But the hospital did not acquire that name until June, 2008. In other words, it seems clear that at least part of the “coup plan” was actually put together years after the plot was alleged to have taken place.

The strangeness doesn’t end there. The Ergenekon indictment makes a number of assertions that, to put it mildly, don’t inspire much confidence in the sophistication of the prosecutors making the case. Among other things, the indictment claims that the American Mafia is an “ethnic terrorist organization” run by the Pentagon, and that the National Intelligence Organization, Turkey’s premier spy agency, is under the “complete control” of the C.I.A. Ergenekon, the indictment claimed, planned to “manufacture chemical and biological weapons and then, with the high revenue it earned from selling them, to finance and control every terrorist organization not just in Turkey but in the entire world.” Despite such obvious fabrications, more than three hundred Turkish officers were convicted and imprisoned last year in the Sledgehammer case.

For years, Erdoğan and his supporters have claimed that the Ergenekon and Sledgehammer prosecutions are legitimate pursuits of the remnants of what is known in Turkey as the deep state, a shadowy network of military officers and other Turkish leaders who conspired, sometimes violently, to maintain the secular order enshrined by Mustafa Kemal, or Atatürk, who founded the Turkish republic on the ashes of the Ottoman Empire, in 1923. For years, the deep state was a reality in Turkish politics. During the Cold War, the military overthrew elected civilian governments three times. To Erdoğan’s credit, he has tamed the Turkish military, modernized the Turkish state, and led the country in a decade of unparalleled economic growth.

But the evidence now suggests overwhelmingly that the Ergenekon and Sledgehammer cases are frauds, show trials built on fabricated evidence, designed to suppress Erdoğan’s domestic political opponents. Both prosecutions have been condemned by the United Nations and other international bodies. Earlier this year, a group called the International Human Rights Network of Academies and Scholarly Societies asked a group, which included Peter Diamond, a professor of economics at M.I.T. and a Nobel recipient, to look into the cases of eight Turkish academics who have been charged. His conclusion: “Given all the information available to us, there appears to be no credible basis on which to judge any of our eight colleagues guilty of committing the crimes of which they have been accused.”

Still, to a remarkable degree, Erdoğan has succeeded in silencing his critics. One reason is his extraordinary repression of the press. Turkey is one of the largest jailers of journalists in the world: in December, the Committee to Protect Journalists counted forty-nine behind bars. Last month, Yavuz Baydar, a prominent journalist for the newspaper Sabah, wrote an Op-Ed for the Times in which he described a tradition of Turkish media owners caving in to political pressure. He was fired shortly after the piece appeared. And when demonstrators gathered in Taksim Square in June to protest the demolition of a public park, Erdoğan’s government dispersed them.

How does Erdoğan get away with it? One reason, surely, is the silence of the Obama Administration. For all of Erdoğan’s heavy-handed tactics, the White House still sees him as a Middle Eastern moderate, a freely elected Muslim leader who is friendly to the West. There aren’t many of those. So, to a remarkable degree, Erdoğan gets a pass. Last week, two days after the conviction of Şirin and the two hundred-plus others in the Ergenekon trial, Erdoğan spoke on the phone with President Obama. According to a White House press release, the two leaders talked about the upheavals in Egypt and Syria.

But not a word about what’s happening in Turkey itself.

Photograph by Adem Altan/AFP/Getty

Read Dexter Filkins on Erdoğan and his ambitions.