Here’s a detailed look at the $25M Ethereum MEV mistrial involving the Peraire-Bueno brothers and its impact on future crypto cases.
The MEV case against MIT-educated brothers Anton and James Peraire-Bueno has just ended in a mistrial.
This outcome has raised new questions about how courts have (and should) handle disputes that involve technical blockchain activity, code execution and intent.
The case also tested whether a complex exploit should fall under traditional fraud and money laundering laws.
How the Mistrial Unfolded
A federal jury in New York spent three weeks reviewing evidence related to a 2023 exploit that removed $25 million in digital assets from Ethereum users. The defendants were two MIT-educated brothers, Anton and James Peraire-Bueno.
Prosecutors argued that the two ran a scheme that relied on MEV bots to target trades and extract funds.
MISTRIAL: Crypto Bros trial US v Peraire-Bueno after three weeks just ended in a mistrial, Inner City Press which live tweeted it all spoke with family members and juror afterwards, it’ll all be in book (very) soon: Code Is Law Lives On? 1: https://t.co/68q2sSDFbB pic.twitter.com/xByWylHm0w
— Inner City Press (@innercitypress) November 8, 2025
Judge Jessica Clarke declared a mistrial after jurors said they could not reach a unified position. Reports from Inner City Press said the group remained divided after several days of discussion.
Their disagreement blocked any decision on guilt or innocence.
Prosecutors said that the brothers set up a plan that involved tricking Ethereum users. They claimed that the pair pretended to be legitimate MEV-Boost validators to gain access to trades they could exploit.
However, the defence said the entire process fell within the technical rules of the blockchain. They compared the action to taking advantage of an opening in a game. They said no fraud occurred because the system behaved as designed.
Why the Ethereum MEV System Was Important to the Case
The debate was focused on Ethereum’s MEV system. Think of MEV as the extra funds a trader or validator can gain by changing the position of transactions inside a block.
This can involve front-running or sandwiching trades by paying higher fees to move ahead of others. In this case, the pair allegedly planned their move for months. However, the actual extraction happened within 12 seconds.
The government said the brothers carried out a bait-and-switch operation. Prosecutors said they acted with the intent to mislead traders who believed they were interacting with a normal MEV process.
They said the brothers used research, planning and private messages that showed clear intent to deceive.
Defence lawyers challenged this idea. They said that the brothers used open blockchain tools that were available to the public. They said that nothing that the pair did required misleading users or pretending to act as anything other than participants in a permissionless system.
At the end of the day, the defence demanded that courts should avoid calling technical behaviour a crime when the blockchain itself does not forbid it.
Intent and Why Jurors Struggled
This trial showed how difficult it can be for courts to evaluate events in defi. Jurors had to decide whether the pair acted with criminal purpose. Many parts of the trial focused on mens rea, or the legal term for proving intent behind a crime.
Reports from Inner City Press show that jurors had trouble applying this idea to technical code-based operations. Defence lawyer Looby said the government tried to narrow how intent should be described.
#breaking: Mistrial in US v. Peraire-Bueno declared by Judge Clarke at 6:53 pm on 18th day of Low Carb Crusader v. Sandwich Attack Bot trial. So, Is Code Law? Code May Be Law? Open to title suggestions : ) Book coming https://t.co/WCnbZyOq6E
— Inner City Press (@innercitypress) November 7, 2025
He said that the accused believed they acted within the rules of the system. Prosecutors replied that the brothers acted with a wrongful purpose and used code as a cover for a scam.
Judge Clarke said the current law does not require the defendants to know whether their actions were illegal. Instead, it focuses on whether the action itself was part of a plan to deceive or take funds.
That comment showed how old legal rules must now fit modern digital behaviour.