Turkish voters will decide Sunday whether to replace the Turkish Republic's parliamentary form of government with a strong presidency. It's a vote that could alter — or, opponents say, endanger — the democratic traditions of this key U.S. ally. Turkey is a NATO member helping fight ISIS.
If the referendum passes, it will increase the power of President Recep Tayyip Erdogan. Polls released late in the campaign showed a narrow lead for "yes," with a large number still declaring themselves undecided. Erdogan is predicting at least a 55 percent margin for "yes."
The vote comes at a perilous time. Turkey remains under a state of emergency declared last July, following a failed coup that left nearly 300 people dead. The Erdogan government has used the emergency powers to conduct a sweeping purge of the military, judiciary and civil service. More than 100,000 people have been fired or arrested, including more than 100 journalists.
In this atmosphere, referendum opponents say it's difficult to run an effective campaign. Government officials dismiss this concern, noting that France is holding elections this spring while under a state of emergency following terrorist attacks in Paris.
The pro and con arguments
Supporters say the change will bring stability and efficiency to a government that has often been paralyzed by infighting. They note that Turkey has had 64 governments since the 1920s, rivaling Italy for instability. They say a stronger government will be better at fighting terrorism; the country has suffered several recent attacks.
Critics and analysts such as the Venice Commission, part of the Council of Europe, a 47-nation pact of European countries including Turkey, say it's "a dangerous step backwards in the constitutional democratic tradition of Turkey," warning of "the dangers of degeneration of the proposed system towards an authoritarian and personal regime."
The current system
Under the existing constitution, Turkey's chief executive is the prime minister, chosen by the parliament. Until recently, the president was an appointed position serving as head of state, not head of government — similar to the queen of England.
Erdogan served as prime minister from 2002 until 2014, when he became Turkey's first president elected by the voters. He immediately announced that he would be a "different kind of president," and has taken a much more active role in running the government than his predecessors.
What would change
Power would be more concentrated under the presidency.
If the referendum is approved by majority vote, the office of prime minister would be abolished after the next elections, scheduled for 2019. Another body, the Council of Ministers, would also go, and all executive and administrative authority would be transferred to the president's office.
The current setup requires the president to be nonpartisan.
Under the new system, the president would no longer have that limit. Erdogan could formally rejoin the party he co-founded, the ruling Justice and Development Party (AKP). Erdogan resigned from the party when he became president.
The change would increase Erdogan's influence over who runs for Parliament.
Cabinet ministers would no longer have to be members of Parliament and the Parliament would not have power over Cabinet appointments — ministers would be appointed directly by the president.
If the referendum is approved, the Parliament would have reduced oversight powers.
There is one change the referendum would bring that is being applauded by pro-democracy groups: the abolition of military courts.
Under the current constitution, Erdogan can run for a second five-year term in 2019 and serve until 2024. Under the proposed changes, Erdogan could have his term limit effectively reset and stay in power through 2029.
Critics say there's a loophole that could give him even more years in the job than that. If Parliament calls snap elections during a second term, he has the option of running for a third.
What happens after the vote?
Assuming the referendum passes, most of the changes it contains won't take effect until the next set of elections, due in 2019. But two important provisions would kick in shortly after the vote. Erdogan would be able to reclaim his position as head of the ruling party, and he would gain new authority to appoint members to the council that oversees the naming of judges and prosecutors.
Opponents of the referendum say this could badly weaken the judiciary's independence, removing another check on presidential power.