People are preparing for the seventh referendum in Turkey's history, which will be held on April 16. Even though most polling companies envisage a victory for the "yes" front, none suggest a clear win; a neck and neck race is expected.In Sunday's cliffhanger referendum, people will vote on 18 amendments to the Constitution, including switching from a parliamentary to a presidential governing system. The reforms would hand executive powers to the president and abolish the post of prime minister. The president would also be allowed to keep his ties to a political party.The "yes" vote stands out when examining past referendums, as five of the six referendums since the first one in 1961 was approved by the people; only one, in 1988, was rejected.

1961

Turkey's first referendum occurred in July 1961 following a military coup, 16 years after the transition to a multi-party system. A new constitution, prepared by the National Unity Committee, which consisted of putschist generals, was voted on in a referendum, with 61.7 percent voting "yes," thus, a new constitution replaced the 1924 constitution.

1982

Ironically, the "coup constitution" only lasted until another military coup on Sept. 12, 1980, when Chief of Staff Gen. Kenan Evren overthrew the government and seized power along with the military chain of command. The putschist generals established the National Security Council, which ordered an advisory council to prepare a new constitution that was voted on in a referendum in November 1982; it received 91.3 percent of the vote, with not even one "contrarian" province. Undoubtedly, Turkish Armed Forces (TSK) pressure, the use of transparent ballot envelopes and anarchy in the streets caused this overwhelming result.

1987

Seven years after the 1980 military coup, the third referendum took place to lift the political ban imposed on prominent politicians from all political wings, such as Necmettin Erbakan, Alparslan Türkeş, Süleyman Demirel and Bülent Ecevit, by the National Security Council, as 50.16 percent voted "yes" and 49.84 percent voted "no."

1988

After the lifting of the ban, Turkey started to return to normal political life, and in September 1988 the following year, people voted to apply municipal elections one year earlier. The fourth referendum witnessed the first and only referendum rejection, as 65 percent voted "no."

2007

From 1982 to1988, three referendums were held. Nineteen years later in 2007 the next referendum was held.

The Justice and Development Party (AK Party), which came to power in 2002 and had been enjoying a majority in Parliament, was probably not considering holding a referendum in 2007. However, a presidential election crisis emerged, compelling the party to hold a referendum to pave the way for the public to directly elect the president, instead of Parliament.

When the term of 10th President Ahmed Necdet Sezer was nearing its end in May 2007, the AK Party nominated Abdullah Gül for president, and he was expecting to be easily elected since his party had an almost two-third majority in Parliament.

However, the Supreme Court ruled that a majority of deputy votes was not enough to elect a president and that two-thirds of Parliament, 367 of the 550 deputies in Parliament, should be present and participate in the election.

Since the Republican People's Party (CHP), the only opposition party at that time, boycotted the election, Gül could not become president despite receiving 352 votes from AK Party deputies. The Constitutional Court overturned the election since the quorum requirements were not met. That same day, the TSK published an e-memorandum and covertly threatened the AK Party government, stating that they would "intervene in the election process if needed."

After the crisis, the AK Party called for early elections; and the people's reaction against the Constitutional Court and the TSK's hostile and biased attitude against the AK Party was reflected in the ballot boxes, as the party got 47 percent of the votes in the July 2007 elections. Afterwards, the Nationalist Movement Party (MHP) entered Parliament and participated in a new presidential election. Eventually, Abdullah Gül was elected the 11th president of Turkey.

However, to prevent such a crisis in the future, the AK Party held a referendum concerning the direct election of the president by the public. It was approved by 68.9 percent.

2010

The sixth and last referendum was held in 2010 to make constitutional changes to the structure of higher judicial bodies; it was approved by 57.9 percent.