A deputy to former national security adviser John Bolton appears unwilling to withdraw his lawsuit confronting whether President Donald Trump can lawfully block current and former aides from speaking to House impeachment investigators, in spite of their recent decision to rescind a subpoena demanding his testimony.

Charles Kupperman, a former deputy national security adviser, filed a lawsuit against House Democrats and Trump last month seeking clarity on whether he should comply with a congressional subpoena seeking his testimony or follow the White House’s instructions to not cooperate. Rather than litigate that question, the House earlier this week withdrew its subpoena, arguing that the move should render the case moot and cause it to be dismissed.