The BBC is seeking to subpoena Donald Trump Jr. Ivanka Trump and Jared Kushner as part of its defense against President Donald Trump's $10 billion defamation lawsuit, according to a Friday court filing by the broadcaster's attorneys.

The lawsuit centers on a BBC Panorama documentary about the Jan. 6, 2021, Capitol riot. Trump filed the suit against the broadcaster, and the BBC is now arguing in court that depositions and documents from three members of the president's family are necessary to mount its defense.

The subpoenas target the president's eldest son, his daughter and his son-in-law—three people who were central figures in the political environment surrounding Jan. 6 and who held close advisory and family roles within the Trump orbit during that period. The BBC's attorneys laid out that argument in the Friday filing without specifying publicly what documents or testimony they believe the three hold that bear on the case.

At $10 billion, the suit is among the largest defamation actions ever filed against a news organization. Trump brought the action as a sitting president, adding political weight to an already high-profile legal confrontation between the White House and a major international broadcaster.

The BBC has not publicly detailed every specific claim Trump contests in the documentary, but the broadcaster is pressing forward aggressively in discovery—the pretrial phase in which both sides gather evidence—by reaching into the president's immediate family circle for materials and sworn testimony.

For the BBC, the subpoena strategy carries real risk. Pursuing depositions from Trump family members in an active lawsuit against a sitting U.S. president is an unusual legal posture for any defendant, let alone a foreign public broadcaster. If a court quashes the subpoenas, the BBC loses a discovery avenue it has publicly argued it needs. If the subpoenas are enforced, Trump Jr. Ivanka Trump and Kushner face the prospect of producing documents and sitting for depositions in a case their father brought.

Kushner served as a senior White House adviser during the first Trump administration and remains close to the president. Ivanka Trump also held a formal White House advisory role during that term. Trump Jr. was a prominent campaign surrogate and public voice for his father around the time of Jan. 6. The BBC's decision to subpoena all three suggests its legal team believes each holds information directly relevant to the documentary's claims.

No ruling on the subpoenas had been reported in court filings available as of Friday. The BBC's attorneys filed the request; whether a judge grants, narrows or blocks it will determine how broadly the broadcaster can gather evidence before trial.

The case is in U.S. federal court, meaning U.S. discovery rules apply even though the BBC is a British public institution funded by the U.K. license fee. That jurisdictional reality is what makes the subpoena strategy viable—American civil procedure gives defendants broad discovery rights, and the BBC is invoking them fully.

Trump's legal team had not issued a public response to the Friday filing as of the time of this report.