* Two former Libor traders send complaints to London police
* Third trader takes advice on following suit
* FCA says to scrap Libor by end-2021
LONDON, July 27 (Reuters) - Two former Libor traders, one of whom has been convicted for conspiracy to rig the global interest rate benchmark, have complained to the police about an expert witness used by the Serious Fraud Office in four trials over rate manipulation.
Tom Hayes, a British former UBS and Citigroup trader jailed in 2015, and Ryan Reich, an American former Barclays trader acquitted this year, have sent reports to the Metropolitan Police about the conduct of SFO witness Saul Haydon Rowe, Hayes's lawyer Karen Todner said on Thursday.
Alex Pabon, an American former Barclays trader convicted in a Libor case last year, is taking legal advice on following suit, his wife Julie said.
Hayes and Reich allege that Rowe, the SFO's chief banking witness and a former director of Turing Experts, between 2014 and 2017 might have misled the SFO, the defence, judges and juries during four criminal trials.
"I hereby ... request that you conduct an investigation as to whether or not Mr Rowe has committed criminal offences, including but not limited to perverting the course of justice, perjury, fraud by false representation, fraud by failing to disclose information and contempt of court," said a report by Todner on behalf of Hayes sent to the Metropolitan Police on Wednesday, which was seen by Reuters.
Rowe denied in court this year that he had misled the SFO and jurors about his expertise, according to a transcript of court proceedings. Rowe, a former trader, who resigned from Turing Experts on June 12, was not immediately available for comment. A spokesman for Turing Experts declined to comment.
The Metropolitan Police confirmed it had received requests for advice about witness testimony. "The content of that correspondence awaits assessment," it said in a statement.
LIBOR UNDER SPOTLIGHT AGAIN
Rowe testified in four SFO Libor trials by providing expert evidence on banking and trading, such as short-term interest rate (STIR) trading, and interpreted communications with or between rate derivatives traders presented in court.
But when Reich was re-tried this year, after a previous jury was unable to reach a verdict in his case, Rowe admitted breaching court rules by contacting others during breaks in the court proceedings to check he understood terms about which he was testifying as an expert.
The SFO paid Turing Experts more than 410,000 pounds ($530,000) since February 2014, according to a Freedom of Information request. The SFO declined to comment on Thursday.
Scrutiny of Libor cases is growing as a U.S. appeals court on July 19 overturned the convictions of two British ex Rabobank traders over the use of compelled testimony in their trials.
Britain's Criminal Cases Review Commission, which investigate cases where people have lost an appeal but believe they have been wrongly convicted, agreed in April to review Hayes's case to see whether it could be referred back to the Court of Appeal, a spokesman confirmed.
Hayes, who is serving an 11-year jail sentence, and Pabon, sentenced to two years and nine months, are among five men convicted in Britain for conspiracy to rig the London interbank offered rate (Libor), a benchmark for rates on trillions of dollars of financial contracts. Eight others have been acquitted.
Pabon was released in March but cannot find a job with a fraud conviction, according to his wife Julie. He last month applied to serve further grounds of appeal against his conviction because of Rowe's evidence at his trial, according to court filings.
Andrew Bailey, the head of the Financial Conduct Authority (FCA), said on Thursday Libor would be scrapped by the end of 2021 and replaced with an alternative benchmark.
($1 = 0.7693 pounds) (Reporting by Kirstin Ridley. Editing by Jane Merriman)