Administration official's noncompliance with unchallenged legislative subpoena in furtherance of an enumerated power of the congress is sufficient concrete injury for Article III standing.
As the rules of the House delegate the subpoena power to the committee plaintiff, the harm is sufficiently particularized.
Appearance with sought documents would redress the harm.
Absent questions of individual particularized harm, separation of powers concerns do not inherently implicate standing.
Judicial enforcement of legislative subpoenas is the longstanding practice, doesn't disrupt balancing between legislative and executive since challenges to the subpoenas can be disputed, and much of the relevant precedent deals with the standing of individual legislators.
Dissent:
Judicial interference has only been the norm for about 40 years, other mechanisms exist.
Dissent:
Justiciability implicates injury-in-fact, as the analogy between harming a person and harming a branch of government is imprecise; separation of powers is inherently a consideration proper to standing analysis; denial of enumerated prerogative opens the door too widely; would permanently entangle the DC Circuit in the oversight process; Scotus has never resolved an interbranch dispute; unlike the Senate, the House has no legislative authority to seek judicial enforcement of subpoenas; even assuming standing arguendo, House plaintiff has no statutory or equitable cause of action; judicial enforcement diminishes the threat of impeachment.