Leon Good-Faith Exception: When a Defective Search Warrant Still Produces Admissible Evidence
A court’s conclusion that a search warrant lacked probable cause does not necessarily mean the evidence will be suppressed.
That surprises many criminal defendants.
The reason is the Leon good-faith exception.
In United States v. Leon, 468 U.S. 897 (1984), the Supreme Court held that evidence obtained by officers acting in objectively reasonable reliance on a search warrant may remain admissible even when the warrant is later determined to be invalid.
As a result, challenging a federal search warrant often involves two separate questions:
First: Was the search warrant supported by probable cause?
Second: If probable cause was lacking, did the officers nevertheless reasonably rely on the warrant under Leon?
A defendant can win the first argument and still lose the motion to suppress because of the second.
Federal criminal defense attorney Michael J. Petro has more than 35 years of experience representing individuals in federal criminal investigations and prosecutions involving search warrants, electronic evidence, motions to suppress, and Fourth Amendment violations.
What Is the Leon Good-Faith Exception?
The Fourth Amendment generally requires search warrants to be supported by probable cause.
The exclusionary rule can prevent the government from using evidence obtained through an unconstitutional search.
But the Supreme Court has explained that suppression is designed primarily to deter police misconduct.
In Leon, police obtained a search warrant from a judge, executed it, and discovered incriminating evidence. The warrant was later found insufficient.
The Supreme Court concluded that excluding evidence does not necessarily serve the deterrent purpose of the exclusionary rule when officers objectively and reasonably relied upon a warrant issued by a neutral judge.
That became known as the good-faith exception.
A Warrant Creates a Strong Government Argument for Good Faith
When an officer presents an affidavit to a judge, obtains a warrant, and then conducts the search within the warrant’s scope, the government has a substantial argument that the officer acted reasonably.
The officer did what the Fourth Amendment ordinarily encourages:
The officer asked a judge for authorization before searching.
But obtaining a judge’s signature does not automatically end the inquiry.
Leon recognizes circumstances in which an officer’s reliance on the warrant is not objectively reasonable.
Leon Does Not Save Every Defective Warrant
The good-faith exception has important limits.
Reliance on a defective warrant may not be objectively reasonable when:
- The issuing judge was misled by information the affiant knew was false or would have known was false except for reckless disregard for the truth;
- The issuing judge wholly abandoned the neutral judicial role;
- The affidavit was so lacking in indications of probable cause that official reliance on it was entirely unreasonable; or
- The warrant was so facially deficient that an officer could not reasonably presume it was valid.
These limitations are critical.
A search warrant is not constitutional simply because a judge signed it.
The Probable-Cause Question and Leon Question Are Different
Defense counsel should keep the two issues separate.
The first question asks:
Did the affidavit establish probable cause?
The second asks:
Even if it did not, was the officer’s reliance on the warrant objectively reasonable?
Those standards are different.
An affidavit can fall short of establishing probable cause while still containing enough factual information to prevent it from being considered obviously deficient.
In that situation, a court may find:
No probable cause — but no suppression because Leon applies.
That is precisely why a search-warrant challenge should address both issues.
Courts Can Decide Leon Without Deciding Probable Cause
In some cases, a reviewing court may proceed directly to the good-faith issue.
If the court concludes that the officers unquestionably relied on the warrant in objective good faith, it may determine that suppression is unavailable without definitively resolving whether the issuing judge actually had probable cause.
For defense counsel, this means it is not enough to prepare an excellent probable-cause argument.
The motion should anticipate the government’s Leon response.
What Is a Bare-Bones Affidavit?
One important limitation on Leon concerns an affidavit so lacking in indicia of probable cause that no objectively reasonable officer could rely on it.
This is sometimes described as a bare-bones affidavit.
A bare-bones affidavit generally contains conclusions or suspicions without sufficient underlying facts.
For example:
“I believe the defendant is selling drugs, and evidence will be found at his residence.”
That is a conclusion.
The issuing judge needs facts allowing an independent determination of probable cause.
Boilerplate Does Not Automatically Establish Probable Cause
Search-warrant affidavits frequently contain standardized language based upon an officer’s training and experience.
For example:
“Drug traffickers commonly maintain records, currency, firearms, and evidence of drug transactions at their residences.”
Or:
“Individuals who possess illegal digital images commonly retain those images on electronic devices.”
Such statements can be relevant.
But boilerplate should not replace facts connecting:
this defendant
to
this criminal activity
and
this place or device to be searched.
The defense should identify which portions of the affidavit contain case-specific evidence and which portions merely contain generalized assumptions.
The Nexus Requirement Remains Important
Probable cause to believe a person committed a crime does not automatically establish probable cause to search every location associated with that person.
The government ordinarily must establish a sufficient nexus between the suspected criminal activity and the place to be searched.
For example:
Evidence that a person sells drugs
is not necessarily identical to:
Evidence that drugs or trafficking records will be found inside that person’s residence.
When the affidavit lacks that connection, defense counsel may challenge probable cause.
The government may then argue that, whatever the affidavit’s weakness, officers could still reasonably rely on the judge’s determination.
That is where Leon becomes critical.
Stale Information Can Undermine a Search Warrant
Probable cause must exist when the warrant is issued.
Information may therefore become stale.
There is no universal rule saying information becomes stale after a specific number of days.
Courts examine factors such as:
- The nature of the crime;
- Whether the conduct was isolated or continuing;
- The type of evidence sought;
- How long the evidence would ordinarily remain at the location;
- The nature of the property searched; and
- Other facts suggesting continued possession.
Staleness can affect both probable cause and the reasonableness of an officer’s reliance on the warrant.
United States v. Pappas
The original version of this article discussed United States v. Pappas, No. 09-1595, a Seventh Circuit case illustrating the power of the Leon good-faith exception.
Pappas was charged with possession of child pornography.
Investigators learned that another individual had sent multiple emails containing illegal images to an America Online email account belonging to Pappas.
Federal agents eventually sought a warrant to search Pappas’s residence.
A federal magistrate judge issued the warrant.
During execution of the warrant, investigators obtained statements from Pappas and discovered illegal images on his computer.
Pappas moved to suppress the evidence and his statements.
The district court granted the motion.
The government appealed.
The 18-Month Delay Created a Staleness Issue
An important problem with the warrant was timing.
Approximately 18 months passed between transmission of the emails containing the illegal images and issuance of the search warrant.
Pappas argued that this information was too stale to support probable cause.
The Seventh Circuit recognized that the age of information is relevant to probable cause.
But there is no automatic rule establishing when information becomes too old.
The nature of the evidence matters.
The court ultimately concluded that, even if probable cause was questionable, the officers could reasonably rely upon the warrant under Leon.
Pappas Demonstrates Why Winning Probable Cause May Not Be Enough
The government made an important strategic argument on appeal.
It essentially argued:
Even if the warrant lacked probable cause, the evidence should not have been suppressed because the agents reasonably relied on the warrant.
The Seventh Circuit agreed.
That illustrates why defense counsel challenging a search warrant should not stop after showing a probable-cause defect.
The defense must ask:
Why was reliance on this particular defective warrant objectively unreasonable?
Consultation With a Prosecutor Can Support Good Faith
Another fact mattered in Pappas.
Before seeking the warrant, the federal agent consulted with an Assistant United States Attorney concerning whether probable cause existed.
The agent then prepared a nine-page affidavit and presented it to a federal magistrate judge.
The Seventh Circuit considered the consultation with the prosecutor additional evidence supporting the officer’s objective good faith.
That does not mean consultation with a prosecutor automatically establishes good faith.
But it can strengthen the government’s argument that the officer was attempting to comply with the Fourth Amendment rather than deliberately circumvent it.
A Detailed Affidavit Can Strengthen the Leon Argument
The government is in a stronger position when an officer:
- Conducts an investigation;
- Documents the evidence;
- Prepares a detailed affidavit;
- Consults with a prosecutor;
- Presents the affidavit to a neutral judge;
- Obtains a warrant; and
- Searches within the warrant’s scope.
Even if a reviewing court later identifies a probable-cause problem, those circumstances may support a finding of objective good faith.
The defense, therefore, must identify something more than a technical defect when arguing that Leon should not apply.
False Statements Can Defeat Good Faith
The situation changes dramatically when the officer obtains the warrant using information the officer knows is false or provides with reckless disregard for the truth.
Leon does not protect deliberate or reckless deception of the issuing judge.
This overlaps with the principles of Franks v. Delaware, 438 U.S. 154 (1978).
A judicial officer cannot make a legitimate probable-cause determination if the officer seeking the warrant deliberately corrupts the information used to make that decision.
Franks v. Delaware
Under Franks, a defendant can seek to challenge material false statements used to obtain a search warrant.
Obtaining a Franks hearing generally requires a substantial preliminary showing.
The defense must do more than demonstrate that some fact in the affidavit was incorrect.
The issue involves whether the affiant intentionally or recklessly included materially false information and whether that information was necessary to the probable-cause determination.
When the required showing is made, the court can examine the affidavit after correcting the alleged falsehood.
Material Omissions Can Also Be Important
Search-warrant problems are not limited to false statements affirmatively placed in an affidavit.
An officer may also omit important information.
For example, an affidavit might emphasize incriminating statements from an informant while omitting significant facts undermining that informant’s reliability.
Depending upon the circumstances and governing law, a deliberate or reckless material omission may support a Franks challenge and undermine the government’s attempt to invoke Leon.
The defense should therefore ask both:
What did the officer tell the judge?
and
What important information did the officer fail to tell the judge?
Informant Credibility Can Affect Leon
Warrants based upon confidential informants deserve particularly careful examination.
Relevant questions include:
- Was the informant previously reliable?
- Did the informant have firsthand knowledge?
- Was the information corroborated?
- Did the informant make statements against penal interest?
- Did police conduct a controlled purchase?
- Was the informant anonymous?
- Did the affidavit disclose facts bearing on credibility?
An affidavit that completely omits critical information concerning an informant’s reliability may present both probable-cause and good-faith issues.
Your website already discusses this problem in the separate United States v. Glover article, in which the Seventh Circuit remanded for a Franks hearing after the warrant affidavit omitted information regarding the informant’s credibility.
The Issuing Judge Must Remain Neutral
Another limitation on Leon applies when the issuing judge wholly abandons the neutral and detached judicial role.
The Fourth Amendment requires meaningful judicial review.
The judge cannot simply serve as a rubber stamp for law enforcement.
This limitation is important because the justification for Leon depends heavily upon the officer having submitted the proposed search to an independent judicial officer.
If genuine independent review disappears, the rationale for good-faith reliance becomes substantially weaker.
Facial Defects Can Defeat Good Faith
An officer also cannot reasonably rely upon a warrant that is obviously defective on its face.
A warrant should particularly identify the place to be searched and the persons or things to be seized.
A facially deficient warrant may give officers such broad or unclear authority that reliance on it cannot reasonably be characterized as good faith.
This creates an important connection between the Leon doctrine and the Fourth Amendment’s particularity requirement.
Particularity Is Different From Probable Cause
Probable cause asks whether sufficient facts justified the search.
Particularity asks whether the warrant adequately limited what police were authorized to search and seize.
A warrant can potentially have one problem without the other.
Defense counsel should therefore examine:
Probable cause
Nexus
Staleness
Particularity
Truthfulness of the affidavit
and
Leon good faith
as separate but related issues.
Cellphone Warrants Can Raise Leon Issues
Modern cellphone warrants can authorize searches through enormous quantities of private information.
A smartphone may contain:
- Text messages;
- Emails;
- Photographs;
- Videos;
- Location information;
- Financial records;
- Internet history;
- Contacts;
- Notes; and
- Application data.
When a warrant broadly authorizes access to digital information, the defense should examine both the factual nexus and the warrant’s particularity.
If the warrant is later found defective, the government may invoke Leon.
The defense must then address whether reliance on that particular digital warrant was objectively reasonable.
Computer Searches Can Present Similar Problems
Computer warrants frequently involve large quantities of data unrelated to the suspected offense.
Important questions can include:
- Why did investigators believe evidence would be on the computer?
- What evidence were they authorized to seek?
- What time period was relevant?
- What files or categories were described?
- Was the warrant effectively unlimited?
- Did officers remain within its scope?
Again, a finding that the warrant was defective may only begin the suppression analysis.
Leon may become the government’s next argument.
Evidence Found Cannot Retroactively Establish Good Faith
Suppose officers execute a weak search warrant and discover overwhelming evidence of a crime.
That discovery cannot retroactively strengthen the affidavit.
The constitutional analysis focuses on what was known and presented before the search occurred.
Likewise, good faith is evaluated based upon the circumstances surrounding the officers’ reliance on the warrant—not on whether the search happened to be successful.
Finding incriminating evidence does not prove the warrant was valid.
The Search Must Remain Within the Warrant’s Scope
Leon concerns reasonable reliance upon a warrant.
It does not give officers permission to disregard the warrant’s limitations.
If a warrant authorizes a search for particular evidence in particular locations, officers must remain within the lawful scope of that authority.
Evidence obtained because officers exceeded the warrant can present a different Fourth Amendment issue.
A valid warrant is not a general search license.
The Exclusionary Rule Focuses on Police Deterrence
Understanding Leon requires understanding the modern exclusionary rule.
Suppression is not treated simply as an automatic consequence of every Fourth Amendment violation.
The Supreme Court focuses heavily on whether excluding evidence would meaningfully deter unlawful police conduct.
When officers reasonably rely upon a warrant issued by a judge, the Court has reasoned that suppressing evidence may provide little deterrent benefit.
But when officers act dishonestly, recklessly, or in objectively unreasonable reliance on an obviously deficient warrant, the deterrence rationale becomes much stronger.
Why the Officer’s Conduct Matters
A strong Leon analysis, therefore, examines what the officer actually did.
Did the officer:
- Conduct a meaningful investigation?
- Corroborate information?
- Prepare a detailed affidavit?
- Disclose weaknesses in the evidence?
- Consult a prosecutor?
- Seek judicial approval?
- Accurately describe the facts?
- Remain within the warrant’s scope?
Or did the officer:
- Submit unsupported conclusions?
- Hide important contrary facts?
- Misrepresent evidence?
- Rely entirely on boilerplate?
- Present an obviously stale allegation without supporting circumstances?
- Seek an unlimited general warrant?
Those distinctions can determine whether reliance was objectively reasonable.
Defense Counsel Should Attack Leon Separately
A motion to suppress based upon a defective warrant should ordinarily contain a separate analysis addressing good faith.
The structure might be:
1. The affidavit failed to establish probable cause.
Then:
2. The Leon good-faith exception does not apply.
The second section should explain precisely why reasonable officers would have recognized the warrant’s defect.
Simply repeating the probable-cause argument may not be enough.
A Bare-Bones Affidavit Presents the Strongest Leon Challenge
One of the strongest defense arguments arises when the affidavit contains so little factual support that no reasonable officer could find probable cause.
The government cannot convert an obviously deficient affidavit into reasonable police conduct merely by obtaining a judicial signature.
The defense should identify:
- Missing facts;
- Unsupported conclusions;
- Lack of corroboration;
- Missing nexus;
- Unexplained staleness;
- Unreliable sources; and
- Excessive reliance on boilerplate.
The cumulative weakness may demonstrate that reliance was objectively unreasonable.
Pappas Shows How Difficult the Leon Standard Can Be
Pappas is a useful warning for defense counsel.
The district court granted suppression.
Yet the Seventh Circuit reversed.
The appellate court concluded that the officers reasonably relied upon the warrant despite the substantial passage of time and the defendant’s challenges to boilerplate language in the affidavit.
The lesson is straightforward:
Showing that probable cause was weak is not necessarily enough.
The defense should establish why a reasonable officer should have recognized that weakness before executing the warrant.
The Four Leon Exceptions Should Be Examined in Every Case
When the government invokes good faith, defense counsel should systematically ask:
Did the affiant knowingly or recklessly mislead the issuing judge?
Did the judge abandon the neutral judicial role?
Was the affidavit so lacking in indicia of probable cause that reliance was objectively unreasonable?
Was the warrant so facially deficient that officers could not reasonably rely upon it?
Those are the principal paths for defeating the government’s Leon argument.
Leon Does Not Make Search-Warrant Challenges Futile
The good-faith exception is powerful.
But it does not mean search warrants cannot be successfully challenged.
Search-warrant litigation remains important when:
- The affidavit is bare bones;
- The officer materially misrepresented evidence;
- Critical information was recklessly omitted;
- The nexus is essentially nonexistent;
- The warrant is facially deficient;
- The issuing judge abandoned neutrality; or
- Other circumstances make reliance objectively unreasonable.
The particular facts determine the outcome.
The Central Lesson of the Leon Good-Faith Exception
When challenging a search warrant, the defense should never stop with:
“There was no probable cause.”
The next question must be:
“Why couldn’t a reasonable officer rely on this warrant?”
That is the practical importance of United States v. Leon.
And United States v. Pappas demonstrates the consequences of the distinction.
Even when probable cause is questionable, evidence can remain admissible if the government establishes objectively reasonable reliance on the warrant.
A successful suppression motion, therefore, should address both sides of the search-warrant analysis.
Experienced Federal Search Warrant Attorney
Michael J. Petro has more than 35 years of criminal defense experience representing individuals in federal criminal investigations and prosecutions involving search warrants and Fourth Amendment issues.
When federal agents search a home, business, cellphone, computer, or other property pursuant to a warrant, defense counsel should examine much more than whether a judge signed the warrant.
The defense should analyze:
- Probable cause;
- Nexus;
- Staleness;
- Informant reliability;
- False statements;
- Material omissions;
- Particularity;
- Scope of the search; and
- The government’s anticipated reliance on the Leon good-faith exception.
If you are facing a federal criminal prosecution involving a search warrant, motion to suppress, defective warrant, cellphone search, computer search, or other Fourth Amendment issue, contact federal criminal defense attorney Michael J. Petro to discuss whether the government’s evidence can be challenged.