Recall commentary in the United States after the crash of Malaysian Airlines Flight 17 in eastern Ukraine on July 16, 2014. Western observers made these points, with some urgency:

• We have to secure the crash scene. Put yellow crime tape around it. Don’t leave it in control of Russian separatists, who control it now. They are the ones suspected of launching the missile that brought the plane down, so they have all incentive to hide and destroy evidence of what happened.

• We have to allow access by impartial investigators. That’s not easy, in a war zone, but we have to do it. Only impartial investigators, not Russian separatists and their allies in Moscow, can learn exactly how this plane crash occurred.

• Thirdly, we want to treat the crash scene with respect. We don’t want looting or tardy removal of bodies. We should return remains of the dead to their families as soon as we can.

These points are instructive because they take us to the period after September 11, 2001, when Europe and the rest of the world so hoped we – someone – would conduct a proper investigation of the attacks that occurred that day. Instead, the United States government declined to conduct any investigation at all. American authorities secured the crash scenes in Manhattan, Shanksville, Pennsylvania, and Washington, DC, not in order to gather and evaluate evidence, but to clear the evidence away as quickly as possible.

Consider the attack on the Pentagon, for example. Every crime scene investigator will say, the first rule is to leave everything exactly where it is, for investigators need to map out pieces of the plane, location of bodies, gather samples for laboratory testing, and so on. Instead, people from the FBI, the very agency we expected would conduct an investigation, cleared away evidence from the Pentagon attack as quickly as they could. The same story, on a larger scale, occurred in Manhattan. Authorities scooped up steel from the Twin Towers and shipped it overseas as expeditiously as they could. Shanksville tells the same story: secure the crash scene not to investigate it, but to clear away evidence so no one can investigate it.

So it goes when people want to hide the truth. The people who fired on Flight 17 near Donetsk bragged about bringing down a Ukrainian military transport plane. They actually posted a video – look what we did! – until they discovered their actual target had been a civilian airliner. Then they deleted evidence of their careless wartime act immediately. When you launch a surface-to-air missile at a civilian aircraft by mistake, you don’t apologize. You remove the evidence. The Russians have already blamed the Ukrainians for bringing down the airliner. Now they must destroy all evidence that contradicts the accusation.

After 9/11, those who controlled all three crime scenes had to cover their guilt. The same has already happened with the people who brought down Flight 17 over Ukraine. The mobile missile launcher is gone. Investigators say you have to leave the scene intact. Otherwise the evidence cannot reveal the truth. When you clean up the scene as fast as possible, as Johnson did with Kennedy’s limousine, you cannot retrieve the stuff you washed away, removed, and destroyed. More recently, after the Germanwings crash in the French Alps, investigators treated the crash scene with care. They found the voice recorder, and quickly publicized the truth about why the crash happened.

In 2001, a shocked American public largely accepted the government’s account of what happened on September 11. People in Europe were more skeptical. They would have liked to see a real investigation. By the time President Bush acceded to pressure, and created the 9/11 Commission in 2002, the evidence at all three locations was long gone. With no crime scene evidence to analyze, the commission instead wrote a treatise about how to prevent future attacks, and of course about the dangers posed by groups like Al Qaeda. The commission did not do any of the things you would expect an investigative commission to do. It couldn’t. The evidence investigators need to analyze to determine what happened was gone.

So when we call for an impartial, international investigation of what happened in eastern Ukraine on July 16, 2014, we can think of a season, not so many years ago, when the rest of the world wanted to see a similar level of openness here in the United States. We know that Russia followed our example from 2001, not our words of admonishment in 2014, when they decided what to do about an investigation of the crash scene in Ukraine.

Russian security forces maintained control of the crash scene until the evidence was gone. In the short run, not coming clean always appears less costly than its opposite, telling the truth. In the long run, officials who want to to hide their complicity in something bad – like shooting down an airliner or blowing up a skyscraper – don’t think that distrust from people they don’t see, and never will see, is all that high a price to pay. They just don’t want to be caught out. If you want to hide your complicity and guilt, you must remove and destroy evidence of that guilt. This pattern of concealment has become so common that we do not expect honesty from public officials any longer. We used to call it, euphemistically, the credibility gap. Now this kind of public dishonesty is taken for granted. Trust ought to bind leaders to their followers, but if you have a lot to hide, trust is the last thing on your mind.