The rate-rigging conviction of former Deutsche Bank trader Christian Bittar was overturned by the Court of Appeal on Friday, despite his guilty plea to the charges in 2018. The ruling means eight of the nine rate-rigging convictions secured in the United Kingdom have now been quashed, leaving just one standing — and marking yet another setback for the Serious Fraud Office (SFO), the UK agency charged with prosecuting serious economic crime. It also raises an uncomfortable question: what should courts do in misconduct cases where jurors were misled about the relevant law?

A guilty plea undone

Bittar was sentenced to five years and four months in 2018 for conspiracy to defraud. He is the first trader in a Euribor or Libor case to have a conviction overturned after admitting the charges.

His attorney, Adrian Darbishire, argued that the prosecution did not need to establish that Bittar agreed to submit “false or misleading” rates.

“I have waited a very, very long time for this day,” Bittar said.

The Court of Appeal's written opinion is expected shortly, setting out the court's full reasoning. Jason Williams of the SFO said the agency had hoped for a different outcome but respects the ruling, as reported by Reuters.

Why the convictions are unravelling

Friday's reversal follows the UK Supreme Court's July 2025 judgment in favor of traders Carlo Palombo and Tom Hayes. The judges held that juries had been misinformed: a rate submission can only be regarded as false if a trader's business interests played a role in it. Jurors therefore needed to determine whether submissions were made on the basis of the submitter's correct assessment.

The cases trace back to the global scandal over manipulation of Libor and Euribor — benchmark rates used to price trillions of dollars in loans and derivatives worldwide — which triggered prosecutions on both sides of the Atlantic.

Overturned, not exonerated

Even so, the Supreme Court found there was “ample evidence on which a jury, properly directed, could have found the appellant guilty.” An overturned conviction, however, is not exoneration.

On Wednesday, the Court of Appeal quashed five more convictions — those of former Barclays traders Alex Pabon, Jay Vijay Merchant, Jonathan Mathew, Philippe Moryoussef and Colin Bermingham. Dame Vera Baird KC, chair of the Criminal Cases Review Commission — the independent body that sends possible miscarriages of justice back to the appeal courts — said there were “no distinguishing factors” between those cases and the earlier appeals.

The regulators' separate ledger

The criminal reversals do not erase regulatory findings. In 2018, the Financial Conduct Authority banned Bittar after receiving evidence of 81 requests for Euribor fixings. The regulator also fined him £426 million across seven separate cases of benchmark-related offenses.

Deutsche Bank paid $775 million in US criminal penalties in 2015, and penalties across US and UK authorities totaled roughly $2.519 billion, according to the US Justice Department.

Euribor still carries the system

Euribor underpins more than €100 trillion in financial instruments and contracts, with a panel of 20 contributing banks. Because the rate serves as a reference point for mortgages, corporate loans and derivatives across the eurozone, even questions about how it is set matter well beyond the trading floor. After Cecabank's departure from the market in September, European regulators said the benchmark remains reputable. Independent research by the Reserve Bank of Australia highlights how thin trading and highly concentrated markets can affect the reliability of the benchmark.

A warning label for crypto reference rates

The issue matters for crypto as well. Cryptopolitan reported that FalconX executed forward rate agreements tied to the Treehouse Ethereum Staking Rate, a benchmark for ether staking yields. As crypto derivatives mature, traders will need to trust not just the rates they use, but the rules behind them.