IF DAVID VELA, President Trump’s nominee to lead the National Park Service, has not already watched the video of U.S. Park Police officers shooting Bijan Ghaisar last November, he should watch it now. Because until and unless Mr. Vela addresses that event, he will likely find himself at the helm of an agency irredeemably stained by Ghaisar’s senseless death.

Ghaisar, a 25-year-old accountant from McLean, was unarmed. There is no sign he had ever owned a firearm; nor did he have a criminal record. The video does not show him doing anything that would justify the U.S. Park Police officers drawing their weapons, let alone pulling the trigger and shooting him in the head, repeatedly.

Yet 10 months later, not a word of explanation has been offered — not by the Park Police, which reports to the National Park Service, nor by the FBI, to which the Park Police referred the investigation. Nor have the Park Police officers who opened fire been identified — an increasing rarity in an era when police departments nationally, under growing public pressure, have handled shootings with a greater sense of accountability.

If he is confirmed by the Senate, this problem should be front and center for Mr. Vela, a 28-year Park Service veteran who is now superintendent of Grand Teton National Park. The shots that killed Ghaisar were fired by police in an agency that would come under his direct jurisdiction. It is unacceptable to say, as officials have until now, that no information will be forthcoming while the matter is under investigation. As many police departments elsewhere have recognized, an investigation does not preclude the release of basic information when a person has been shot to death by officers.

The video of Ghaisar’s shooting, made by a Fairfax County police cruiser’s dashboard camera, is clear as can be. It shows a Park Police patrol car pursuing the vehicle driven by Ghaisar as he drives along the George Washington Memorial Parkway. Ghaisar had been rear-ended in a minor fender bender a few minutes earlier. Imprudently, he drove off.

When Ghaisar pulls over, the Park Police officers approach his car with guns drawn and pointed at him — an unconventional tactic following a minor road accident, to put it mildly. Ghaisar drives off. That happens again a few minutes later. The third time he pulls over, in the Fort Hunt area of Fairfax County, the officers leap from their patrol car, again with guns drawn. This time, as Ghaisar’s vehicle begins slowly to roll away from them, they open fire at point-blank range. He died 10 days later.

Ghaisar’s family, having exercised superhuman patience for months, last month filed suit against the government, seeking $25 million in damage — and an explanation. The congressman who represents the area where the shooting occurred, Rep. Don Beyer (D-Va.), asked for a meeting with relevant officials, including FBI Director Christopher A. Wray — and was rebuffed. The wall of official silence, coverup and unaccountability has so far not been breached.

That is unacceptable. It should be topic No. 1 for Sen. Lisa Murkowski (R-Alaska), who leads the Senate committee that will consider Mr. Vela’s nomination. And, if he is confirmed, it should be at the top of his priorities on Day One.

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