The proposals would abolish the post of prime minister, enabling the president to centralise all state bureaucracy under his control and appoint cabinet ministers.
They are backed by the ruling Justice and Development Party (AKP)
and some right-wing nationalists.
“Turkish people want stability and strong leadership,” says former AKP MP Emin Dihnar. “Turkey doesn’t need any more coalitions. Turks have shown that they want strong government.”
For the AKP the coalition governments that preceded its victory in the 2002 general election proved incapable of governing efficiently and improving living standards.
“Our country started having elections in the 1950s,” says Nedim Yamali, an AKP official running the Yes campaign in Ankara. “Since then the only times we have been a strong country have been when we have been ruled by one party. Under our AKP governments for the past 15 years average income has risen from 3,500 dollars [3,300 euros] a year to 10,500 dollars [8,895 euros] a year.
“Before us, in the 30 years between 1970 and 2000, there were 30 different governments established and collapsed and the average annual income only went up about 1,000 dollars.”
Erdogan takes most of the credit for that and he is idolised by millions of supporters.
But press freedom has been curtailed in recent years and, following a failed coup last year, a state of emergency has led to 134,000 state employees being fired and 47,000 people jailed. So the reform’s opponents say it will give an already-authoritarian president even more power.
“That’s a big lie,” Yamali exclaims. “Today you can’t put the president on trial, he can only be prosecuted for treason, apart from that he can do what he wants. And, if his party has the majority in parliament as it is now, he has all the power and he answers to nobody. President
Erdogan is putting himself in a position where he can be prosecuted and 400 MPs can force him to resign with a vote of no confidence.”
The Republican People's Party (CHP) is leading the No campaign, which is also supported by left-wing groups, notable the pro-Kurd People’s Democratic Party (HDP), and some right-wing nationalists.
Speaking at the CHP’s huge Ankara headquarters, the party’s vice-president Tekin Bingol says it is unfair to blame coalitions for all the country’s past problems and points out that its economy is beginning to flag today.
“Today we have unemployment, low-level economic crisis, lots of problems in our foreign policy and they have been ruling the country for 15 years by themselves,” he says.
“There’s no coalition today and there’s no stability, either.” If voters reject the proposals that will be good not just for Turkey but for the whole troubled region, he claims.
“If the No wins, people will relax a bit,” Bingol claims. “Turkey will become calmer. The Middle East will calm down. Tension is so high at the moment, people feel anxious. That will disappear. The elected government will continue to govern but consensus will have to be the new way of doing things in parliament. This constitutional change will be off the agenda and parliament will start working more efficiently.”
Sunday’s referendum may not deliver the peace, prosperity and efficiency being promised by both sides. But, whatever its outcome, it will make history.