NEW YORK (Reuters) - A former UBS AG (>> UBS AG) trader charged as part of a U.S. investigation into Libor rate manipulation lost a bid to have the case dismissed on Monday, with a federal judge ruling that a fugitive from U.S. justice had no right to mount a legal challenge.

U.S. District Judge Paul Crotty in Manhattan said Roger Darin, a Swiss citizen, was "flouting judicial process" by remaining in his home country to avoid arrest while sending lawyers to ask the judge to dismiss the case.

Darin's lawyers argued he was not a fugitive since he had never fled, let alone appeared, in the United States since the U.S. Justice Department filed its criminal complaint in 2012.

But Crotty said his ruling was in line with "the realities of modern criminal prosecutions."

Bruce Baird, Darin's lawyer, in a statement said: "We think the judge misunderstood and misapplied the law, and we look forward to an appeal."

A Justice Department spokesman did not respond to a request for comment.

The decision came hours after Tom Hayes, Darin's co-defendant, was sentenced in a related case in London to 14 years in prison after being found guilty of conspiring to rig Libor benchmark interest rates.

The U.K. case was the first to reach trial in a global inquiry that has led to several people being charged and some of the world's most powerful banks and brokerages paying around $9 billion in regulatory settlements.

Libor, or the London interbank offered rate, is a short-term rate that underpins hundreds of trillions of dollars of financial products from mortgages to credit card loans.

According to U.S. authorities, Darin, who while at UBS worked in Singapore, Tokyo and Zurich, was primarily focused on trading yen-dominated short-term interest rate derivative products.

The complaint said Darin conspired with Hayes to commit wire fraud by agreeing to submit yen Libor opinions to benefit Hayes' positions.

Darin has never appeared in U.S. court, and Switzerland does not extradite its citizens. A federal magistrate judge in March recommended rejecting Darin's arguments.

A Japanese subsidiary of UBS in 2012 pleaded guilty to wire fraud as part of a $1.5 billion accord resolving U.S., U.K. and Swiss probes.

In resolving a similar investigation into the rigging of currency markets, UBS AG itself in May pleaded guilty and agreed to pay a $203 million penalty for breaching a non-prosecution agreement over manipulation of Libor.

The case is U.S. v. Hayes, et al, U.S. District Court, Southern District of New York, No. 12-mj-03229.

(Reporting by Nate Raymond in New York; Editing by Tom Brown)

By Nate Raymond

Stocks treated in this article : UBS AG, UBS Group AG