“We granted rehearing en banc in this case to decide what standard of proof the government must satisfy to show that the evidence would ultimately have been discovered through lawful means without the constitutional violation. Must it show there was a reasonable probability of ultimate discovery, or show by a preponderance of the evidence that the evidence ultimately would have been discovered?” The preponderance standard is adopted, and all prior cases to the contrary on the “reasonable probability” standard are overruled. United States v. Watkins, 2021 U.S. App. LEXIS 24893 (11th Cir. Aug. 20, 2021) (en banc):
The primary problem with using the reasonable probability standard of proof to predict whether evidence discovered through a constitutional violation ultimately would have been discovered anyway is that no one knows exactly what reasonable probability means in this context. The words are plain enough separately, but their combined meaning is anything but plain. The term “reasonable probability” implies there must be an unreasonable probability, just as darkness must exist for light to have meaning. Otherwise, why put the limiting adjective “reasonable” in front of the noun “probability” — what work does “reasonable” do? But how can a probability be unreasonable? How does a reasonable probability differ from an unreasonable one? In the 41 years that the term “reasonable probability” has been the guiding standard in this circuit for an important exception to the exclusionary rule, it has never been defined in this context. Probably because no one knows exactly what it means here.
To be sure, the Supreme Court has crafted “reasonable probability” as a relatively new term of art for use in other areas of the law. See generally Borden v. United States, 141 S. Ct. 1817, 1828 (2021) (“[T]erms of art depart from ordinary meaning.”) (quotation marks omitted). The most famous example is use of “reasonable probability” as the standard of prejudice in ineffective assistance of counsel cases. In Strickland the Court undertook the task of deciding the appropriate measure of prejudice where counsel’s performance fell outside the broad scope of reasonable professional assistance. Strickland v. Washington, 466 U.S. 668, 691-96 (1984). The guiding star for the Court’s analysis was that “[t]he purpose of the Sixth Amendment guarantee of counsel is to ensure that a defendant has the assistance necessary to justify reliance on the outcome of the proceeding.” Id. at 691-92. Given that purpose, the Court reasoned that “not every error [of counsel] … undermines the reliability of the result of the proceeding.” Id. at 693. It considered making the prejudice standard whether counsel’s deficient conduct “more likely than not altered the outcome in the case,” which would have required a defendant to show by a preponderance of the evidence that counsel’s errors had determined the outcome. Id. at 693-94. But the Court rejected that “outcome-determinative standard” as “not quite appropriate.” Id.
. . .
So what standard of proof should be used to determine if the ultimate discovery exception applies? We think the wisest course is to follow the Supreme Court’s lead in Nix and use the preponderance of the evidence standard. Even putting aside — as we are here — what Bourjaily says about it, Nix at a minimum holds that preponderance of the evidence is a permissible standard of proof here. See Nix, 467 U.S. at 444 & n.5. It provides a green light for use of that standard of proof of ultimate discovery. No Supreme Court decision green lights use of the reasonable probability standard for ultimate discovery purposes.
The preponderance standard of proof is one of widespread and longstanding use. See Concrete Pipe & Prods. of Cal., Inc. v. Constr. Laborers Pension Tr. for S. Cal., 508 U.S. 602, 622 (1993) (noting that the burden of showing something by a preponderance of the evidence is “the most common standard in the civil law”); United States v. Trainor, 376 F.3d 1325, 1331 (11th Cir. 2004) (“[T]he term ‘preponderance of the evidence’ is a common law term of longstanding use.”). Its meaning is simple, straightforward, and clear. “A preponderance of the evidence is evidence which is more convincing than the evidence offered in opposition to it.” Metro. Stevedore Co. v. Rambo, 521 U.S. 121, 137 n.9 (1997) (quoting Greenwich Collieries v. Dir., OWCP, 990 F.2d 730, 736 (3d Cir. 1993)) (cleaned up). It “simply requires the trier of fact to believe that the existence of a fact is more probable than its nonexistence.” Concrete Pipe, 508 U.S. at 622 (quotation marks omitted) (quoting In re Winship, 397 U.S. 358, 371-72 (1970) (Harlan, J., concurring)). Or phrased in a slightly different fashion, it is proof that persuades the trier of fact that a proposition “is more likely true than not true.” United States v. Deleveaux, 205 F.3d 1292, 1296 n.3 (11th Cir. 2000) (quoting a jury instruction that was upheld); see also 11th Cir. Pattern Civ. Jury Instr. 1.1 (2020) (stating that the standard of proof by a preponderance of the evidence means the party with the burden “must prove that, in light of all the evidence, what [that party] claims is more likely true than not”).
The preponderance standard is well-defined; the reasonable probability standard is undefined in our case law for use in this context. The preponderance standard is unambiguous and clear; the reasonable probability standard is ambiguous and vague in this context. The preponderance standard is straightforward and simple to apply; the reasonable probability standard is not in this context. Use of the preponderance standard in this context has the Supreme Court’s good judging seal of approval; use of the reasonable probability standard does not.
Even if Nix does not mandate use of the preponderance standard, we hold that the standard of predictive proof the government must satisfy in order to establish the proper application of the ultimate discovery exception is preponderance of the evidence, not reasonable probability. All of our decisions holding to the contrary are overruled.
"If it was easy, everybody would be doing it. It isn't, and they don't." —Me
"Life is not a matter of holding good cards, but of playing a poor hand well." –Josh Billings (pseudonym of Henry Wheeler Shaw), Josh Billings on Ice, and Other Things (1868) (erroneously attributed to Robert Louis Stevenson, among others)
“I am still learning.” —Domenico Giuntalodi (but misattributed to Michelangelo Buonarroti (common phrase throughout 1500's)).
"Love work; hate mastery over others; and avoid intimacy with the government."
—Shemaya, in the Thalmud
"It is a pleasant world we live in, sir, a very pleasant world. There are bad people in it, Mr. Richard, but if there were no bad people, there would be no good lawyers."
—Charles Dickens, “The Old Curiosity Shop ... With a Frontispiece. From a Painting by Geo. Cattermole, Etc.” 255 (1848)
"A system of law that not only makes certain conduct criminal, but also lays down rules for the conduct of the authorities, often becomes complex in its application to individual cases, and will from time to time produce imperfect results, especially if one's attention is confined to the particular case at bar. Some criminals do go free because of the necessity of keeping government and its servants in their place. That is one of the costs of having and enforcing a Bill of Rights. This country is built on the assumption that the cost is worth paying, and that in the long run we are all both freer and safer if the Constitution is strictly enforced." —Williams v. Nix, 700 F. 2d 1164, 1173 (8th Cir. 1983) (Richard Sheppard Arnold, J.), rev'd Nix v. Williams, 467 US. 431 (1984).
"The criminal goes free, if he must, but it is the law that sets him free. Nothing can destroy a government more quickly than its failure to observe its own laws, or worse, its disregard of the charter of its own existence." —Mapp v. Ohio, 367 U.S. 643, 659 (1961).
"Any costs the exclusionary rule are costs imposed directly by the Fourth Amendment."
—Yale Kamisar, 86 Mich.L.Rev. 1, 36 n. 151 (1987).
"There have been powerful hydraulic pressures throughout our history that bear heavily on the Court to water down constitutional guarantees and give the police the upper hand. That hydraulic pressure has probably never been greater than it is today." — Terry v. Ohio, 392 U.S. 1, 39 (1968) (Douglas, J., dissenting).
"The great end, for which men entered into society, was to secure their property." —Entick v. Carrington, 19 How.St.Tr. 1029, 1066, 95 Eng. Rep. 807 (C.P. 1765)
"It is a fair summary of history to say that the safeguards of liberty have frequently been forged in controversies involving not very nice people. And so, while we are concerned here with a shabby defrauder, we must deal with his case in the context of what are really the great themes expressed by the Fourth Amendment." —United States v. Rabinowitz, 339 U.S. 56, 69 (1950) (Frankfurter, J., dissenting)
"The course of true law pertaining to searches and seizures, as enunciated here, has not–to put it mildly–run smooth." —Chapman v. United States, 365 U.S. 610, 618 (1961) (Frankfurter, J., concurring).
"A search is a search, even if it happens to disclose nothing but the bottom of a turntable." —Arizona v. Hicks, 480 U.S. 321, 325 (1987)
"For the Fourth Amendment protects people, not places. What a person knowingly exposes to the public, even in his own home or office, is not a subject of Fourth Amendment protection. ... But what he seeks to preserve as private, even in an area accessible to the public, may be constitutionally protected." —Katz v. United States, 389 U.S. 347, 351 (1967)
“Experience should teach us to be most on guard to protect liberty when the Government’s purposes are beneficent. Men born to freedom are naturally alert to repel invasion of their liberty by evil-minded rulers. The greatest dangers to liberty lurk in insidious encroachment by men of zeal, well-meaning but without understanding.” —United States v. Olmstead, 277 U.S. 438, 479 (1925) (Brandeis, J., dissenting)
“Liberty—the freedom from unwarranted intrusion by government—is as easily lost through insistent nibbles by government officials who seek to do their jobs too well as by those whose purpose it is to oppress; the piranha can be as deadly as the shark.” —United States v. $124,570, 873 F.2d 1240, 1246 (9th Cir. 1989)
"You can't always get what you want / But if you try sometimes / You just might find / You get what you need." —Mick Jagger & Keith Richards, Let it Bleed (album, 1969)
"In Germany, they first came for the communists, and I didn't speak up because I wasn't a communist. Then they came for the Jews, and I didn't speak up because I wasn't a Jew. Then they came for the trade unionists, and I didn't speak up because I wasn't a trade unionist. Then they came for the Catholics and I didn't speak up because I wasn't a Catholic. Then they came for me–and by that time there was nobody left to speak up."
—Martin Niemöller (1945) [he served seven years in a concentration camp]
“Children grow up thinking the adult world is ordered, rational, fit for purpose. It’s crap. Becoming a man is realising that it’s all rotten. Realising how to celebrate that rottenness, that’s freedom.” – John le Carré, The Night Manager (1993), line by Richard Roper
"The point of the Fourth Amendment, which often is not grasped by zealous officers, is not that it denies law enforcement the support of the usual inferences which reasonable men draw from evidence. Its protection consists in requiring that those inferences be drawn by a neutral and detached magistrate instead of being judged by the officer engaged in the often competitive enterprise of ferreting out crime." —Johnson v. United States, 333 U.S. 10, 13-14 (1948)
The book was dedicated in the first (1982) and sixth (2025) editions to Justin William Hall (1975-2025). He was three when this project started in 1978.