Prime Minister Victor Ponta's leftist Social Liberal Union (USL) is trying to oust suspended President Traian Basescu. Ponta accuses Basescu of abusing his position to block government legislation, but the European Union has regarded some of the government's moves as undermining democracy.
The row has stalled policymaking in Romania, delayed vital economic reforms and raised concerns over the Balkan state's International Monetary Fund-led aid deal.
An impeachment referendum held on 29 July yielded an 88% majority in favour of removing the centre-right Basescu, but the turnout did not reach the 50% threshold required by the Constitutional Court.
Court set to decide on referendum by end of August
The Court was expected to invalidate the plebiscite but has put off its ruling until 31 August, and asked to see voter lists to assess the true size of the electorate after USL officials asserted that the actual number of voters was much smaller.
On Tuesday, the president of the Venice Commission – the Council of Europe's advisory body on constitutional matters – said in a statement that the court had asked his panel for help to protect its independence from political pressure.
"It is for me surprising, and even shocking, that for the second time in a short period of time the constitutional court of a member state of the Council of Europe and the European Union feels obliged to appeal to the Venice Commission in order to protect its independence," Gianni Buquicchio said.
He did not say how his commission would respond. Romanian government officials have not commented. They responded to previous EU complaints by saying the court is independent and they would abide by its rulings.
But before the 29 July vote, Ponta's government sought to trim the high court's powers and threatened to replace judges – before concerted pressure from the European Commission, the United States and Germany forced it to back down.
IMF ‘a bit worried’ by Romanian situation
The updated electoral list could potentially show a lower number of registered voters than thought and push turnout above 50%, but most analysts doubt this will happen.
Basescu has lost popularity over his support of austerity policies required to restore confidence under an IMF aid package, and over perceptions that he has engaged in cronyism.
Ponta called on Basescu to resign after the referendum, citing the 88% vote against him. The president replied that there was a majority of voters who did not want him removed from office and he has refused to step down.
The dispute in the corruption-tinged former communist state, which was admitted to the EU in 2007, has sunk the leu currency to record lows and, says the IMF, could further damage the recession-ridden economy.
"We are a little bit worried about the situation and also the impact the political situation has on the economy," IMF mission chief Erik de Vrijer told interim President Crin Antonescu, a Ponta ally.