US senator accuses Turkey's Erdogan of democratic backsliding over jailing of rival

Turkey's authorities should present credible evidence of corruption against Istanbul's jailed mayor or immediately release him, U.S. Senator Adam Schiff said on Thursday as he urged his colleagues to back a resolution calling out President Tayyip Erdogan over what he called democratic backsliding.

Erdogan's main rival, mayor Ekrem Imamoglu, was jailed in March pending trial on corruption charges, sparking Turkey's largest protests in a decade. Popular support for Imamoglu has since risen further above Erdogan, opinion polls show.

The mayor has denied all charges. His arrest triggered market turmoil and accusations of a politicized judiciary that the government has rejected, saying the judges are independent.

Schiff's resolution, seen by Reuters, calls for Erdogan and law enforcement authorities to release Imamoglu or present credible evidence against him, and to uphold democratic values.

"The continued detention of Mayor Imamoglu, as well as the harassment and arrest of dozens of journalists and dissenting political voices in Turkey, is the latest in an unfortunate trend in the democratic backsliding that Turkey has seen under President Erdogan," Schiff said in a statement to Reuters.

"The Senate should send a loud and clear message that the unjustified jailing of Erdogan’s political rivals is not acceptable."

The resolution also urges U.S. Secretary of State Marco Rubio to speak out about the detention and engage Turkey over what it called anti-democratic behavior.

Rubio's State Department has said little on Imamoglu's case, calling it an internal judicial matter for NATO ally Turkey, while calling for human rights to be respected.