By Humeyra Pamuk and Daren Butler
ISTANBUL (Reuters) - Likening foes in the judiciary to medieval "Assassins" betraying Turkey, Tayyip Erdogan made one thing clear as he assumed the presidency last month: his battle to purge their influence over the courts is far from over.
The power struggle has transformed a judicial election next month, normally an unassuming affair, into a key battleground. The vote will decide the members of the High Council of Judges and Prosecutors (HSYK), responsible for the appointments, transfers, promotions and expulsions of the country's top judicial figures.
"It's a matter of life and death for the government," said Murat Aslan, chairman of YARSAV, a secularist association of judges and prosecutors which has prepared a candidate list and will play a key role in the vote.
Erdogan's conflict with U.S.-based Islamic cleric Fethullah Gulen, whose Hizmet, or Cemaat, network he accuses of building a "parallel state" in judiciary and police to usurp his authority, is the main thorn in the side of Erdogan's apparently unstoppable consolidation of power. Gulen denies such ambitions.
It is a battle which has raised concern among diplomats and investors about judicial independence in the EU candidate nation, and which has already seen thousands of police officers and hundreds of judges and prosecutors purged or reassigned.
Opponents fear that should Erdogan succeed in stamping out Gulen's influence and gain greater sway over the judiciary, another layer of checks and balances will be eroded as he forges ahead with plans to create a more powerful presidential system.
Erdogan, his AK party far and away the most popular in the country, faces little opposition in parliament. In stepping up to the presidency, he no longer faces the limited notional checks on his executive power that he faced as prime minister.
Loyalists argue the reverse, saying that an unaccountable and shadowy network, built up over decades, cannot be allowed to control a court system whose credibility has already been massively eroded. Some fear, though, that Erdogan might be underestimating the sheer scale and depth of Gulen sympathizers and struggle to impose his will.
Aslan said if the Gulenists or another faction opposed to the government came out on top, corruption investigations against Erdogan's inner circle which emerged last December could be re-opened, presenting a more poignant challenge.
Ahmet Davutoglu, who succeeded Erdogan as prime minister when he became President, warned last month about the HSYK vote, saying some factions wanted to control the body so that "it hangs like a Sword of Damocles over the political will elected by the people".
DECADES OF INFLUENCE
Gulen, whose followers say they number in the millions, is believed to have built up power in the police and judiciary over decades. Followers have described the moves against them as a witch hunt.
Law professor Osman Can, a member of the ruling AK Party and former reporting judge at the Constitutional Court, said members of Gulen's Cemaat network began entering the judiciary in the mid-1980s, many educated in Gulen's network of schools, and went on to become judges and prosecutors.
"When a decision is made among the top ranks of the Cemaat, when someone hits a button, you see certain figures mobilized," Can told Reuters. "If the Gulenists win the HSYK election it would be an undemocratic result and would not have legitimacy."
A strong showing by Cemaat would not be the end of the story, he added, forecasting it would prompt fresh government efforts to bolster its position by reforming the HSYK.
Legislation in February boosted government influence over the HSYK but the constitutional court canceled some articles of that law two months later.
The struggle with Gulen dogged Erdogan's final months as prime minister, the strength of his hostility towards his former ally illustrated in his references to them variously as "leeches" and later "Hashshashin" (Assassins), a medieval Islamic sect in Persia commonly depicted as trained killers.
"The legal system cannot be abandoned to the blackmail of a handful of Assassins," Erdogan said in his final speech as AK Party leader before assuming office as head of state.
"I believe that patriotic judges and prosecutors will purge the Assassins among them and lift the shadows hanging over the legal system," he said.
(Editing by Nick Tattersall)