Brexit could prevent the prime suspect in the disappearance of Madeleine McCann from being extradited to Britain to face trial, lawyers have said.

Scotland Yard are seeking to have German citizen Christian Brueckner face trial in the UK over the alleged abduction and murder of the young girl, according to the Telegraph. The convicted rapist was first linked to the case of the missing three-year-old’s disappearance in 2022, but has vehemently denied any involvement.

But after Brexit, this could prove legally difficult for the Metropolitan Police as German law forbids extradition of its citizens to non-EU countries.

According to Article 16 of the constitution, German citizens may not be extradited to any foreign countries that are outside of the bloc, despite other agreements that were put in place to prevent such occurrences.

Lawyers and legal experts told The Independent that the likelihood of Brueckner being surrendered to the UK is practically zero.

“Because he is a German citizen, Germany is highly unlikely to extradite him to the UK,” said George Hepburne Scott, a specialist extradition barrister and head of extradition at Church Court Chambers.

“Under the German Basic Law and the post-Brexit EU–UK Trade and Cooperation Agreement, Germany can refuse to surrender its own nationals, and in practice it does.”

The EU-UK Trade and Cooperation Agreement (TCA) came into force in 2021 and covers reciprocal extradition processes. But because of the country’s constitution, it is likely that Article 16 would override its obligations to the UK, now outside of its EU obligations.

In fact, Germany has denied such requests in the past. In September 2023, it refused to extradite an Albanian man accused of drug trafficking on account of the “state of the British prison system”.

Separately, it declined an extradition arrest warrant for a Polish national accused of fraud to be returned to Poland in 2020, due to concerns over the fairness of trial proceedings – a first in its history.

According to The Telegraph, the Metropolitan Police are determined for Brueckner to face charges in Germany, in the event that the country refuses to hand him over to Britain.

But the tensions could spark a diplomatic row, made worse by the UK having less legal entitlement in such events due to Brexit.

“If there is sufficient evidence, the realistic route is for Germany to prosecute him domestically rather than hand him over,” says Scott. “Pre-Brexit the extradition would have been streamlined, fast-tracked and effectively automatic – subject to routine procedural requirements.”

Before Brexit, it would have been much easier to have Brueckner sent over to the UK to stand trial for a suspected crime against a British citizen due to the European Arrest Warrant, experts say.

The fast track process is described as “a simplified cross-border judicial surrender procedure for the purpose of prosecuting or executing a custodial sentence or detention order” by the European Commission.

But despite a replacement extradition scheme, the UK stands on shaky ground for extraditions when it comes to crime across Europe. The only way out would be if Brueckner somehow decided to leave Germany and made himself vulnerable to arrest.

“Following Brexit, the UK and EU negotiated a new extradition scheme which closely matched the European Arrest Warrant,” says Nick Vamos, former head of extradition at the Crown Prosecution Service and now partner at Peters & Peters.

“However, as the UK was now outside the EU, ten countries including Germany exercised the option in Article 83 of the Trade and Co-operation Agreement to impose a ‘nationality’ bar on extraditing their own citizens to the UK.

“In Germany, this is a matter of constitutional law, not political discretion, so there is no possibility of Breuckner being extradited to the UK unless he leaves his home country.”

Furthermore, the CPS are yet to make a decision to request extradition and they must have solid evidence before they do so. It is not sufficient to have someone extradited for the purposes of collecting further information. And even that process faces increased scrutiny due to the UK’s decision to leave the EU.

“The Prosecution in the UK must have made a decision to prosecute before requesting extradition from Germany,” says Richard Cannon, Partner at Stokoe Partnership Solicitors.

“A person can only be extradited to the UK for one of three purposes: to be prosecuted for a criminal offence, to be sentenced after conviction, or to serve a sentence already imposed.

“A person cannot be extradited for the purpose of determining whether there is sufficient evidence to prosecute them or to permit further investigation.

“Extradition from Germany to the UK has become more complex post‑Brexit. We no longer rely on the European Arrest Warrant’s streamlined framework, so requests face increased documentation, longer timelines, and closer judicial scrutiny on issues like dual criminality, proportionality, and the adequacy of assurances.

“Defendants can resist extradition where there is a real risk to fundamental rights, where proceedings would be oppressive due to health or delay, or where fair‑trial and prison‑conditions assurances are insufficient. In practice, careful litigation on human rights, speciality, and procedural safeguards can be decisive in preventing removal.”

A Met spokesperson told The Independent: “The Met’s investigation into the disappearance of Madeleine McCann has been active since 2011. A dedicated team continues to examine the events of the evening of 3 May 2007 in Praia da Luz, while supporting and updating Madeleine’s family.

“As part of ongoing enquiries, we remain in close working discussion with policing colleagues in Germany and Portugal.

“We will continue to pursue any viable lines of enquiry.”

The German government has been contacted for comment.