Justice Alito asked a stellar hypo during arguments in Staub v. Proctor:

JUSTICE ALITO: Could I just ask where -could I ask where your argument leads? Let’s say that an employer calls in an employee and says: Now, we have to decide who to lay off, and we have looked at your record over the last 10 years, and here it is, all the evaluations you’ve gotten over the past 10 years, and based on all of that, we — we’ve decide that you are going to be the person to be laid off. Now if it turns out that one of those evaluations was rendered by someone who had an anti-military bias, would that make the employee — would that be a prima facie case against the employer?
MR. SCHNAPPER: It would. But the affirmative –
JUSTICE ALITO: Even — even if the employer at that time did every — made every reasonable effort to investigate the validity of all the prior evaluations, still the employer would be on the hook?
MR. SCHNAPPER: Yes. There is nothing in the statute or in the common law that creates a special rule for thorough investigation.

Zing. It’s like a Mariano Rivera Cutter. No matter what you do, it’s a strike, and if you take a swing, you’ll miss.

Alito hit the nail on the head, or perhaps in this context, he hit the cat on its paw.
Even Justice Kennedy noticed the sweeping implications of that concession.

JUSTICE KENNEDY: Well, that’s a sweeping rule. I was going to ask a related hypothetical. Suppose the — the officer who is in charge, charged with the decision to terminate or not to terminate says: I’m going to have a hearing. You can both have counsel. And you have who, is it — suppose Buck — suppose the two employees that were allegedly anti-military here testified and they said there was no anti-military bias, and the person is then terminated. Later the employee has evidence that those two were lying. Could he bring an action then?
MR. SCHNAPPER: Yes. Yes.
JUSTICE KENNEDY: That’s sweeping. That’s almost an insurer’s liability insofar as the director of employment is concerned.
MR. SCHNAPPER: It’s –
JUSTICE KENNEDY: He has to insure. He has — he has done everything he can, he has an hearing, and he has almost absolute liability.

Likewise Justice Sotomayor picked up on this hypo:

JUSTICE SOTOMAYOR: Isn’t that — the government’s formulation that the discrimination has to play a substantial role in the termination a limiting principle? I mean, you answered or appeared to be answering Justice Alito that in a 10-year history if one report of discrimination existed that that would shift the burden to the employer.

Is that an accurate statement of law? That one report has to play a role that is more than a mere existence, doesn’t it?

As did Justice Scalia:

JUSTICE SCALIA: Mr. Schnapper, I guess this goes back to Justice Alito’s question. I find it difficult to grasp the distinction that you draw or what is seems could possibly exist between a willful motivating factor and a non-willful motivating factor. I mean, to say that it’s motivating is — is to say that it’s willful, it seems to me. But you want us to draw a distinction between a willful motivating factor and a non-willful motivating factor?

Alito’s hypo caused Kennedy, Sotomayor,and Scalia to take notice, and return to the hypo. Cutter from the one-justice delta force.

Petitioner based his entire argument on absolute liability for respondeat superior under agency law and the Restatement of Agency. I don’t think the Justices are buying that argument.

Alito, looking at the text of the bill rather than principles of agency law, further cornered Schnapper:

JUSTICE ALITO: That isn’t what the statute says. You jump over the language of the statute. It has to be a motivating factor in the decision to discharge. And that speaks — that looks natural — the natural reading of that is that it looks at the motivation of the person who actually makes the decision to discharge. Now, I’m not suggesting that’s the right rule. That’s a very unattractive rule. But the rule that you have suggested is also a very unattractive rule, one that I doubt the Congress intended to adopt. Is there no reasonable middle position here? It’s all or nothing?