Kelly Ghaisar, the mother of Bijan Ghaisar, who was fatally shot by U.S. Park Police in November 2017. (Toni L. Sandys/The Washington Post)

SATURDAY MARKS the first anniversary of the shooting that took Bijan Ghaisar’s life, following a minor fender bender on the George Washington Parkway in which his own vehicle was rear-ended. Unaccountably, Ghaisar, a 25-year-old accountant, drove away; he was followed by a Park Police patrol car, then at least twice failed to heed officers’ instructions to come to a halt. Possibly, he was terrified when the police approached his car with guns drawn, in apparent violation of policy. The third time he pulled over, the officers opened fire. A video, taken by the in-car camera of a Fairfax County police car trailing the Park Police vehicle, recorded the events clearly.

Ghaisar’s actions were foolish. But they did not warrant his execution-style killing by police.

Almost immediately, the investigation was handed off to the FBI by the Park Police. It is being supervised by the U.S. attorney in Washington. And there, in federal officials’ hands, it has languished, month after month — a black hole of official unaccountability, arrogance and contempt for citizens who have demanded an explanation, and for the Ghaisar family, whose anguish is unimaginable.

Virtually no information has been willingly released. Not the names of the two officers who opened fire without apparent justification. Not any official explanation. Even the fact that Ghaisar was unarmed at the time — in fact, he was ardent in his distaste for guns — was divulged in late October only after The Post filed a Freedom of Information Act request with Fairfax police. Last month, Park Police Chief Robert D. MacLean, whose record will be stained indelibly by the Ghaisar case, declined even to confirm that the two officers, whose identities had been given to The Post by a law enforcement source, were employed by his agency.

This is how justice often works, or fails to, in countries where the rule of law has never gained traction, and where governments regard citizens as subjects or nuisances. This is what a coverup looks like — a gloss of bureaucratic folderol and inertia that impedes progress on a case whose complexity involves not the events themselves but the mere fact that police officers, rather than civilians, pulled the trigger. The fact that a conspiracy of official silence is the response to the slaying of an unarmed man in this country is an affront to American values and the rule of law.