The United States Drug Enforcement Administration (DEA) has defended its decision to withhold portions of investigative records connected to a historical criminal investigation involving Nigerian President Bola Ahmed Tinubu, telling a US court that releasing the information could expose confidential sources and reveal sensitive investigative techniques.
The position was contained in a September 23, 2026 filing by the United States government before the United States District Court for the District of Columbia in a Freedom of Information Act (FOIA) lawsuit brought by Aaron Greenspan.
The case, Aaron Greenspan v. Executive Office for U.S. Attorneys et al., concerns requests for records relating to Tinubu and other individuals in connection with a US investigation into an alleged drug-trafficking and money-laundering operation.
In the latest filing, the government defended the DEA’s reliance on several FOIA exemptions to withhold information contained in its investigative records.
The filing referred to a declaration submitted by the DEA, identified as the Davis Declaration, as well as an accompanying Vaughn Index explaining the basis for the agency’s decision to withhold or redact portions of the records.
Greenspan had challenged the DEA’s Vaughn Index, arguing that it contained similar justification paragraphs and entries.
The government rejected the criticism, explaining that the records consisted of similar categories of investigative documents, including DEA-6 Reports, DEA-292 Reports and DEA-210 Reports.
According to the government, because the documents were similar investigative forms and types of law-enforcement records, the justifications for withholding information from them would naturally contain similar reasoning and invoke similar exemptions.
The filing therefore confirms that the records at issue include formal DEA investigative reports connected to the criminal investigation.
One of the most significant issues raised in the government’s response concerns information relating to confidential sources.
The government said the DEA had adequately addressed the potential harm that could result from disclosure of information capable of identifying such sources.
Quoting the DEA’s Davis Declaration, the filing states that information relating to confidential sources “could reasonably be expected to disclose the identity of a confidential source.”
The DEA further maintained that information concerning confidential sources has historically been afforded extensive protection under FOIA.
The agency said it determined that the importance of protecting such information outweighed what it described as the relatively limited public interest in its disclosure.
The DEA’s position is that releasing the information could expose individuals who provided information to law-enforcement authorities and undermine the protections afforded to confidential sources.
The government also defended the DEA’s use of FOIA Exemption 7(E), which permits law-enforcement agencies to withhold certain information concerning investigative techniques and procedures where disclosure could create risks for law enforcement.
The filing said the plaintiff had conceded that the FBI could withhold “non-public details of investigative techniques,” but sought an order compelling the government to produce a redacted ex parte declaration that had been filed under seal.
The government argued that the existence of the sealed declaration did not undermine its reliance on the exemption, particularly because the records arose in the context of what it described as “a criminal investigation of a drug operation.”
The argument indicates that some of the information being withheld could reveal how investigators conducted or documented their investigation, rather than merely identifying individuals involved.
The latest filing forms part of a broader legal battle over historical FBI and DEA records relating to Tinubu and Abiodun Agbele.
In an April 2025 ruling in the same case, US District Judge Beryl Howell addressed FOIA requests seeking criminal investigative records concerning Tinubu and Agbele in connection with a federal investigation into an international drug-trafficking and money-laundering operation.
The earlier proceedings involved requests for records from the FBI and DEA relating to a Nigerian heroin-distribution organisation that was active from approximately 1988 to 1994 or later.
The court record identified “Tinubu, Bola Ahmed” among the individuals referenced in the relevant FOIA request.
Judge Howell’s 2025 ruling also addressed an earlier attempt by the agencies to issue what is known as a Glomar response, under which an agency refuses to confirm or deny whether responsive records exist.
The judge concluded that the government could not rely on that approach under the circumstances because the existence of the investigation had already been officially acknowledged.
The ruling, however, did not establish that Tinubu committed a crime or that the records sought by Greenspan contain evidence of criminal wrongdoing by him.
The September 23, 2026 filing similarly does not disclose the substantive contents of the DEA records concerning Tinubu.
It does not state how many records mention Tinubu, what confidential sources told investigators, whether any source made allegations against him, or whether the DEA found evidence of criminal wrongdoing by him.
It also does not disclose what specific transactions investigators examined or whether the withheld material contains evidence establishing any criminal conduct by Tinubu.
The significance of the latest filing is therefore centred on the continuing legal dispute over access to the records, rather than any new finding of criminal wrongdoing against the Nigerian president.
What the filing establishes is that the DEA has investigative records falling within the scope of the FOIA litigation and is defending its decision to withhold portions of those records under specific statutory exemptions.
The government’s latest position means the fight over the records remains focused on whether the DEA has sufficiently justified its redactions and whether additional portions of the investigative material should eventually be released under US freedom-of-information law.
The court’s eventual handling of the dispute could determine whether more information from the long-running investigation becomes publicly accessible.