* Court extends detention of 3 members of female punk band
* Pussy Riot stormed altar in anti-Putin protest
* Case reignites debate on Orthodox Church political role
By Gabriela Baczynska
MOSCOW, July 20 (Reuters) - Three members of female punk group Pussy Riot who derided President Vladimir Putin in a protest in Moscow's main cathedral had their spell in jail extended by six months on Friday in what their lawyers called a show trial dictated by the Kremlin.
The women, who have been held in pre-trial custody for almost five months, face up to seven years in jail on charges of hooliganism for storming the altar in multi-coloured masks to sing a "punk prayer" to the Virgin Mary to "Throw Putin Out!"
Pussy Riot's brazen act was part of a protest movement against Putin's 12-year dominance of Russia that at its peak saw 100,000 people take part in winter demonstrations in Moscow.
The Feb. 21 protest, which offended many believers in the mainly Orthodox Christian country, exposed deep divisions over the church leadership's backing for Putin and the scale of punishment faced by the women, two of whom have young children.
Defence lawyer Mark Feigin said the court's acquiescence to a prosecution request to hold Maria Alyokhina, Nadezhda Tolokonnikova and Yekaterina Samutsevich until Jan. 13 showed Russian leaders had given orders for their conviction.
"Today's decision only proves again that our role as defendants here is a pure formality," Feigin told reporters after the hearing, which was closed to the media.
"There is a lot of evidence that the judge will disregard justice in favour of pre-set instructions on how to rule which have been handed down by the authorities. They want to find them guilty ... to punish them with real jail time.
"It is not a process but a judicial reprisal," he said.
Putin and the head of Russia's Orthodox Church, Patriarch Kirill, are among more than 30 people that Feigin and his two colleagues want to call to testify as witnesses in the trial.
After the Pussy Riot performance, Kirill said the Church was "under attack by persecutors". The patriarch has often praised Putin and in February likened his 12-year rule to a "miracle of God".
Nikolai Polozov, another defence lawyer, said authority figures were trying to portray the protest as "an attack on Russia by some dark powers".
"It is just a theatre of the absurd, not a real court," Polozov said.
Court spokeswoman Darya Lyakh said a date would be announced on Monday for the start of the high-profile trial, which has drawn comparisons to the jailing of former oil tycoon, billionaire and Putin critic Mikhail Khodorkovsky.
The Pussy Riot hearing on Friday took place in the same court where Khodorkovsky's second trial was held.
Outside, Orthodox Church faithful mingled warily with Pussy Riot backers, some of whom wore T-shirts emblazoned with the band's trademark brightly coloured balaclavas.
A church activist read Bible passages out loud, while one of the women's supporters unfurled a banner saying: "Throw Putin Out!", raising chants of "Freedom! Freedom!" before he was detained.
"Believers' feelings are not worth a prison sentence," read another sign held aloft, before rain dispersed the crowd.
The women's arrest has drawn widespread outrage among human rights groups and opposition activists already fuming over the church's backing of Putin in a presidential election he won in March.
"The authorities have again chosen to take the toughest measures against Pussy Riot," said Tolokonnikova's husband, Pyotr Verzilov. He added that this would "only provoke more outcry in society and provoke more support for the girls."
But some Orthodox believers have called for tough punishment for an act they regard as blasphemous.
"I was really upset at what happened," said Vadim Kvyatkovsky, a member of an Orthodox Christian youth group. "This was no act of art. If it was happening anywhere else, in the street, we could discuss that, but when it is in a cathedral then it just violates our freedoms."
Half of Muscovites surveyed this month by the Levada Center, an independent pollster, said they had negative views about the prosecution of Pussy Riot members while 36 percent said they welcomed the criminal case.
Rights group Amnesty International reiterated its call for the defendants' release, saying they were "awaiting a trial that shouldn't be taking place".
"Even if the three women did take part in the protest, detention on the serious criminal charge of hooliganism would not be a justifiable response to the peaceful - if, to many, offensive - expression of their political beliefs," the group's regional director, John Dalhuisen, said in a statement.
The protest "lasted only a few minutes, the activists left the cathedral when requested to do so and it caused no damage," he said.