Forty-one days after the arrest, the paperwork justifying it is still being written. The document Britain owes the United States by 16 September is not a formality — it is the thing the entire case now depends on.

Britain has until 16 September to produce the full extradition request in the case of Andrew and Tristan Tate. That is forty-one days from the date of this article, and just under two months from the day US Marshals arrested the brothers in Miami on 18 July. Almost everything that will happen in this case between now and next spring turns on what is inside the document Britain has not yet delivered.

Under the US–UK extradition treaty, provisional arrest can precede the full request. This is standard treaty practice and it is entirely lawful. But provisional arrest is meant to be brief, and the treaty imposes a deadline for exactly that reason: the requesting state must convert its provisional showing into a full evidential package within sixty days of the arrest, or the arrested person is entitled to release. The sixteenth of September is that deadline.

The package Britain must deliver is not a summary. It is a formal instrument of extradition, transmitted through diplomatic channels, and it must contain — among other elements required by the treaty — the identity and description of the persons sought; the text of every statute alleged to have been violated; a statement of the facts of the offence, with dates and locations; a summary of the evidence supporting the charges; the arrest warrant issued by a British court; and copies of the charging instruments themselves. Where identity is contested, the package must contain photographs, fingerprints, or comparable identifying material. Where a statute of limitations exists, its inapplicability must be demonstrated. Where the offences are complex — and fifty-nine counts across seven complainants and seven years is complex — the statement of facts must be capable of being read count-by-count.

None of this is optional. If the package is incomplete, or arrives late, or fails to satisfy the treaty's evidential threshold, the American court is not required to certify the case. In the worst outcome for the CPS, the brothers would be released from federal custody without prejudice to any future request — meaning Britain could refile, but the men would be at liberty in the meantime, and there would be no legal mechanism to prevent them leaving the United States.

The 16 September deadline therefore does two things that are worth stating separately. It sets the moment at which Britain must, publicly and formally, put its case on paper. And it sets the moment at which Andrew and Tristan Tate's continued detention either becomes fully authorised or becomes questionable in a way that the courts can act on.

The CPS has said publicly that Bedfordshire Police delivered a further evidential file earlier this year and that the July charging decision followed. What has not been made public is the state of the extradition package itself. That package is a separate document from the charging decision, prepared by a specialist unit within the CPS in consultation with the Home Office and the Foreign, Commonwealth and Development Office. Its assembly involves translation of witness statements into the format required by American federal courts, formal certification by British judicial authorities, and clearance for onward transmission to the US Department of Justice, which forwards the request to the federal prosecutors handling the case in Miami. Each of these steps takes time, and none of them has been reported as complete.

There is a further complication, one the coverage has not addressed. The conduct alleged in the July charges spans July 2010 to August 2017. Some of the material is now more than fifteen years old. Where witness statements have been taken years after the events described, and where physical evidence is limited or absent, the evidential threshold required for extradition — probable cause, in the American formulation — is met by the requesting state's own attestation of sufficiency, but the attestation must be capable of being made in good faith. British prosecutors will need to explain, in the package, why material available in principle for years is now being advanced as the basis for extradition in 2026.

There is also the question of the images and extreme pornography counts, which represent nineteen of the forty-two counts against Andrew Tate and which appear to rest on material seized from electronic devices. Chain-of-custody documentation, forensic analysis reports, and the underlying seizure warrants will all need to be prepared for onward transmission. This is not evidentially difficult in the ordinary case. It is administratively substantial in every case.

The brothers' defence team, led by Joe McBride, will not have sight of the extradition package until it is formally lodged and produced in court. Once it is lodged, the defence has the opportunity to challenge it at the extradition hearing on grounds of legal sufficiency — not on the merits of the underlying allegations, which are reserved for any eventual trial, but on whether the package contains what the treaty requires it to contain. Defective packages have been refused before. They are refused rarely, but they are refused.

The most likely course of events is that Britain files on time, the package is legally sufficient, the magistrate certifies the case, and the matter proceeds to the Secretary of State for a final decision that may take months. The second-most-likely course is that Britain files on time and the package is challenged on specific points, prompting further filings and further delay. The least likely course, but not an impossible one, is that Britain fails to file on time, or files a package that the magistrate finds insufficient, and the brothers walk out of the Miami federal facility while the CPS regroups.

Any of these outcomes is a legitimate outcome of a functioning extradition system. All of them are outcomes in which no allegation against Andrew or Tristan Tate is proven or disproven, because extradition does not decide guilt. It only decides who gets to decide guilt.

For now, both brothers remain in custody. The document that will justify — or fail to justify — that custody is due in forty-one days.

Andrew and Tristan Tate deny all charges and allegations against them. No court has convicted either brother of any offence. Britain's full extradition request is due by 16 September 2026.