The most important "legal" fact is the fact that, once convicted, you're guilty of the crime. Even if you didn't really do it (see Alford pleas, for instance), for all the courts care, you're guilty. It works in reverse, too - if you've been convicted, but that conviction is set aside and you're not retried, you're innocent, at least in the eyes of the law. That's one reason that it bugs me when pro-death penalty people try to poke holes in exonerations by arguing that those folks aren't innocent, they just had their convictions overturned. No conviction means legally innocent, dipshits.
Which is a circuitous way of getting to this article by Garrett Epps over at The Atlantic about the Supreme Court's recent decision in Navarette v. California. The case arose when someone called 911 to report she had been run off the road by a particular pickup truck, giving a description that included the license plate number. Officers found the truck, driving down the road, a while later and, without observing anything illegal or problematic, pulled the truck over, supposedly to make sure the driver wasn't drunk. He wasn't drunk, but he was hauling a good amount of marijuana. He tried, unsuccessfully, the suppress the marijuana as the fruit of an illegal stop.
The issue for the Supreme Court, therefore, was whether the tip to 911 provided enough evidence of wrongdoing to provide reasonable suspicion to support a stop. In making that analysis, it's important that the Court figure out whether the tip was from a known informant or whether it was anonymous. A tip from a known source who has proven to be reliable in the past is pretty much iron clad - it's going to provide reasonable suspicion. An anonymous tip not so much. In a case back in 2000, the Court held that an anonymous tip that does no more than identify a person and make a claim of illegal activity isn't enough to support reasonable suspicion.
So that distinction is kind of important, and it played a role in Navarette. As Epps explains:
As it reached the Supreme Court, thus, Navarette was a case about anonymous 911 callers. But the 911 call in Navarette was not, in what for lack of a better word I will call fact, anonymous at all.
According to the record in the case, the caller gave the 911 operator her name. But at the outset of the trial, the prosecutor summoned the wrong 911 operator and wasn’t able to get the actual recording of the call into evidence. The case had to progress as if the call had been anonymous.
Epps gets the process right, but doesn't appreciate what it means. He argues that judges "get to live in the land of 'conjecture or fiction.'" He goes on:
The majority relies on the idea that anonymous tips won’t happen; in a case where one didn’t happen, is there really any basis to assess whether one will? The dissent says that we don’t know whether the caller in 'the present case' knew that her call wasn’t anonymous. Except, well, we do, since she, well, gave her name. So 'the present case surely' suggests none of the [parade of horribles] Scalia claims it does.
What Epps misses, willfully or otherwise, is that, legally speaking, the call was anonymous. It doesn't matter what some out of court information tells us. The prosecution has a burden of proving the reliability of a tip. One way to do that is to show that it's not anonymous. The prosecution failed to do so in this case, for whatever reason. Therefore, it's an anonymous tip. To treat it otherwise would allow the prosecution to shirk its burden and make its case easier.
Which is not to say that Epps doesn't make some good points. He's correct that both the majority and dissent (a Thomas v. Scalia affair) need to do some mental gymnastics (or "legal mummery" - good phrase) to make their arguments because the tip is treated as anonymous, but that's par for the course. What matters is who stuck the landing at the end of their routine? On this one, it's Scalia.
Think of it in a sporting sense - replay after replay may show that that guy who just scored to knock your team out of the World Cup was offside, but the only reality that matters is that the linesman didn't call it. Same thing in the game that is law - once something becomes a fact, reality takes a back seat.