BUCHAREST (Reuters) - The leader of Romania’s ruling Social Democrats Liviu Dragnea retained control of the party on Friday, defeating dissenters who said his criminal record had made him a liability, but his victory seems likely to heighten political infighting.

A past conviction in a vote-rigging case earned him a suspended jail term which prevented him from being prime minister. And he is due next month to launch an appeal against a three and a half year prison sentence passed in a separate abuse of office case.

He is also under investigation in a third case on suspicion of forming a criminal group to siphon off cash from state projects, some of them EU-funded.

But he emerged unscathed from an eight-hour meeting of the party’s executive committee on Friday at which he won a comfortable majority of support, beating off critics who wanted him out.

Analysts said his latest confrontation with internal party critics might also complicate Dragnea’s and his allies’ efforts to stall the fight against corruption in one of the European Union’s most graft-prone states.

Dragnea led the party to a sweeping victory in a Dec. 2016 parliamentary election, but since then its attempts to weaken the judiciary have dominated the public agenda.

An attempt to decriminalise several corruption offences last year via emergency decrees triggered massive protests and was ultimately withdrawn. Changes to criminal codes this year invited comparisons with Poland and Hungary, which are embroiled in a standoff with Brussels over the rule of law.

Deputy Prime Minister Paul Stanescu, Bucharest mayor Gabriela Firea and lawmaker Adrian Tutuianu - all vice-presidents of the party - called for his resignation, saying his management has hurt the party’s popularity.

Dragnea has previously argued in favour of an emergency decree that would grant amnesty for some corruption offences - potentially affording him protection against prosecution - or retroactively scrap wiretap evidence collected by Romania’s intelligence service SRI on behalf of prosecutors.

After Friday’s executive meeting, Dragnea said Prime Minister Viorica Dancila, a close ally, had not supported the idea of an emergency decree on amnesty at this time.

But Dragnea vowed to continue fighting against what he calls a “parallel state” of prosecutors and secret services who want to bring the party down via corruption trials.

“I personally no longer care an emergency decree regarding amnesty,” Dragnea said. “If the government wants to pass it, it’s up to them, whenever they want.”

“As long as I remain party president I will do all I can to bring down this heinous system that is ruining lives.”

Unlike bills passed through parliament, which can be challenged and take a long time, emergency decrees take effect immediately.

“He (Dragnea) might have broken them (his critics) today,” said Sergiu Miscoiu, political science professor at Babes-Bolyai University. “But he is gradually losing control, his enemies are consolidating and the next round might be fatal.”