In California criminal cases, a motion to suppress evidence is a pretrial motion where you ask the court to exclude (or “throw out”) evidence because it was obtained by way of an illegal search or seizure. These motions are also called “suppression motions” or “1538.5 motions.”1
Here are four key things to know:
- You make 1538.5 motions as part of your preliminary hearing or at a separate pretrial suppression hearing.2
- PC 1538.5 requires courts to suppress evidence obtained from an unreasonable police search done without a search warrant.3
- Courts also must suppress evidence obtained through a deficient search warrant.4
- If the court grants your 1538.5 motion, the D.A. cannot introduce the evidence in question at trial.5
To help you better understand how a Penal Code 1538.5 PC motion to suppress works, our California criminal defense attorneys6 will address the following:
1. 1538.5 Motions
Simply put, California Penal Code section 1538.5 PC authorizes you to move for
- the exclusion of any evidence that is the product of an unlawful search and seizure, and/or
- the return of any property that was illegally seized.7
The former result—suppression of illegally-obtained evidence—is a far bigger priority. This is because the prosecution may not have a solid case against you if that evidence is excluded.
Meaning of “Unlawful Search or Seizure”
Penal Code 1538.5 PC sets out the reasons why a search or seizure may be unlawful—and, by extension, why a motion to suppress the evidence obtained in that search may be granted.
These are:
- The search was performed without a search warrant, and was “unreasonable.”
- The search was performed with a warrant but was unreasonable, for one of the following reasons:
- The warrant was insufficient on its face,
- The property or evidence was not of the type described in the warrant,
- The warrant was issued without probable cause,
- The warrant was executed in a way that violated the California constitution or the U.S. Constitution (for example, the officers conducting the search committed police misconduct), OR
- There was any other violation of state or federal constitutional standards.8
The rationale behind a Penal Code 1538.5 motion goes back to the Fourth Amendment to the U.S. Constitution9—and Article I, Section 13, of the California Constitution.10 These constitutional sections provide that all citizens have the right to be free from unreasonable searches and seizures.11
Example : Travis has been obeying all traffic laws but is pulled over solely because the police were engaging in racial profiling. During the “pat down” search, police discover cocaine in his pocket and arrest him for California Health and Safety Code 11350 HS drug possession.12
As part of the pretrial process, Travis and his attorney file a motion to exclude the cocaine as evidence. They argue that (1) the pat-down search of Travis was done without a warrant in violation of criminal procedure, and (2) the search was unreasonable under the circumstances.
Example : Police suspect George of engaging in theft of power tools, and they search the motel he owns under a warrant that allows them to look for stolen power tools. They find no tools—but they do seize several TV sets that turn out to be stolen. George is charged with receiving stolen property.
The police had a warrant to search George’s motel—but the stolen televisions were not among the things that they had a warrant to search for. Therefore, the seizure was invalid—and George’s motion to suppress evidence with respect to the TV sets is granted.13
Burden of Proof for a Motion to Suppress
The question of who bears the burden of proof—the prosecution or you—on a Penal Code 1538.5 motion to suppress depends on whether or not the search or seizure was conducted without a warrant.14
Specifically:
- If the search was conducted without a warrant, the presumption is that it was unreasonable—and the burden is on the prosecutor to prove that it was actually reasonable;15 BUT
- If the search was conducted with a warrant, then it is presumed to have been legal—and the burden is on you to prove that it was not.16
Whichever side bears the burden of proof has to prove their case by a preponderance of the evidence.17 A “preponderance of the evidence” means that it is more likely than not that the search / seizure was unreasonable.18
Example : Melissa is being charged with sale or transportation of a controlled substance. She and her lawyer plan to argue that the search warrant under which police officers conducted a search of her home was not specific enough with respect to items that the officers were supposed to be looking for.
Because the search was conducted with a warrant, Melissa will bear the burden of showing that the warrant was so vague that it was invalid on its face—and the officers could not have reasonably believed it was valid.
Meaning of “Reasonable Expectation of Privacy”
Before the court will even entertain your 1538.5 motion to suppress evidence, you must prove that you had a “reasonable expectation of privacy” in the place that was searched or the items that were seized.
If you did not have a reasonable expectation of privacy, then
- the search or seizure could not have been illegal, and
- the evidence, therefore, should not be suppressed.19
As San Francisco criminal defense attorney Neil Shouse20 explains,
“This is an objective standard. Whether or not you personally believe you had a ‘reasonable expectation of privacy’ is irrelevant. The issue is whether you had an objectively reasonable expectation of privacy–that is, one that society would be ready to accept as reasonable.”
Places and property in which you do not have a reasonable expectation of privacy in California law include:
- Abandoned property (for example, something thrown away in a wastebasket),21
- A car which you have stolen,22 and
- A car in which you are riding, but in which you have no ownership or other rights.23
Though you do have a reasonable expectation of privacy in
- Your home,
- Your vehicle,
- The contents of your cellphone,
- A tent or tarp designed to shield the inhabitant from public view,24 and
- If you are a public school student, the personal belongings that you bring to school.25
Example: Rich, a robbery suspect, leaves his hotel room without checking out. The motel owner calls the police, who search the motel room without a warrant and find the robbery victim’s stolen possessions. Rich is arrested and charged.
Rich’s subsequent motion to suppress the evidence from in motel room search is not successful. That is because there is no reasonable expectation of privacy in abandoned property, so he had no reasonable expectation of privacy in the room.26
“Derivative” Evidence / Fruit of the Poisonous Tree
In addition to property or evidence that was seized or discovered during an illegal search—a motion to suppress evidence may also apply to other evidence that is the indirect result of an illegal search.27
This is known as “derivative” evidence.28 The legal theory under which it is also suppressed is known as the “fruit of the poisonous tree” doctrine.29
Example : As part of an investigation into a criminal fraud case, police illegally search a computer without a warrant and discover some incriminating electronic files.
They know they cannot seize the computer and use it as evidence—so instead they issue a subpoena to the criminal defendants for those same electronic files. Though those files cannot be used as evidence against the defendants because the police would not have known about them were it not for the illegal search.30
If you try to argue through a Penal Code 1538.5 motion that certain evidence is “fruit of the poisonous tree” and should be excluded, the prosecution will try to get the evidence admitted anyway by arguing one of three theories:
- that the possibly tainted evidence is so far removed from the illegal search or seizure that it does not make sense to enforce the exclusionary rule,31
- that the evidence was found through an independent channel, not just through the illegal search,32 or
- that there is a “reasonably strong probability” that the evidence would have ultimately been discovered even without the illegal search.33

Penal Code 1538.5 PC authorizes you to move for the exclusion of any evidence that is the product of an unlawful search and seizure.
2. 1538.5 Hearings
Misdemeanor Charges
If you face only misdemeanor charges, your criminal defense lawyer may file a 1538.5 motion to suppress evidence as early as your California arraignment.34
As part of the pretrial process, this motion
- must be heard prior to your jury trial, and
- will be argued and ruled on at a special pretrial hearing known as a “suppression hearing.”35
The only exception to this is if you do not discover that evidence against you was illegally obtained until your trial has already begun. In cases like this, you may bring a motion to suppress evidence during the course of the trial.36
Felony Charges
If you face felony charges (or both misdemeanor and felony charges filed in the same case) your lawyer has two options:
- your lawyer may argue this motion at your preliminary hearing (where he/she will be limited to trying to suppress evidence that the prosecutor intends to introduce at that hearing), or
- your lawyer may choose to wait and have the motion to suppress handled at a special suppression hearing devoted only to this issue.37
If your motion is heard (and denied) at the preliminary hearing, you also have the right to file it again, and have it heard in a separate suppression hearing.38 However, the evidence at the suppression hearing will be limited to:
- The transcript of the preliminary hearing, and
- Any evidence that couldn’t reasonably have been presented at the preliminary hearing.39
Suppression Hearings
The suppression hearing is where both sides have the opportunity to argue their positions on the motion to suppress. It takes place before a judge—not a jury.
The suppression hearing will involve some or all of:
- Testimony from you about the illegal search or seizure,
- Testimony from any witnesses who can help your case,
- Testimony from the police involved in the search or seizure,
- Cross-examination of you and your witnesses by the attorney for the prosecution,
- Cross-examination of the prosecution’s witnesses by your lawyer, and
- Oral arguments by your criminal defense attorney and the prosecuting attorney as to why the motion should be granted or denied.
Penal Code 1538.5 suppression hearings are subject to the rules of the California Evidence Code.40 The exception is that hearsay (that is, out-of-court statements that are offered for their truth)—which is not admissible in normal criminal trials—may be admissible at a suppression hearing.41
The Ruling on a Motion to Suppress Evidence
Once the judge has heard all of the evidence, they must decide whether to exclude or admit the controversial evidence—that is, whether to grant or deny the Penal Code 1538.5 motion.
Depending on the circumstances, the judge may also decide to grant the suppression motion in part—excluding some, but not all, of the evidence in question.
If the motion to suppress evidence is granted, the prosecutor’s case against you may well fall apart. They may choose to
- dismiss the charges, or
- negotiate a generous plea bargain.
But if the prosecutor is determined to press forward with the charges anyway, they may also
- appeal the granting of the motion to suppress evidence,42
- dismiss the charges and file a new complaint,
- seek a grand jury indictment, or
- attempt to reinstate the original complaint.43
If the judge rules against you (denies the motion to suppress), the evidence will remain admissible. At that point, you and your attorney will discuss whether you should
- plead guilty or nolo contendere (aka, “no contest”) to the charged offense,
- try to “strike a deal” with the prosecution so that you can plead guilty or nolo contendere (“no contest”) to a reduced charge, or
- proceed to trial.
If your motion to suppress is not granted, you may file an appeal of the ruling—within 30 days of the ruling.44
Proceedings where Suppressed Evidence is Admissible
The rule that illegally-obtained evidence cannot be admitted in a criminal trial—which is known as the “exclusionary rule”—does not apply to all legal proceedings.45
Therefore, even if you win on a motion to suppress evidence, that evidence may still be admissible at
- parole revocation hearings,
- grand jury proceedings, and/or
- civil deportation hearings of immigrants facing deportation for criminal convictions.46
3. Other Pretrial Motions
A Penal Code 1538.5 motion to suppress is only one of several kinds of motions your California criminal defense attorney may choose to file as part of the pretrial process. Others include:
Penal Code 995 PC – Motions to Set Aside the Information
A Penal Code 995 PC motion to set aside the information is essentially a request for the judge to dismiss one or more of the charges against you.47 It makes sense to file this motion if you and your attorney believe that either:
- Your rights were violated during your preliminary hearing, or
- There is no probable cause to charge you with the crime.48
Pitchess Motions
A California Pitchess motion is a request for information contained in a law enforcement officer’s personnel file.49 Criminal defense lawyers typically raise this motion when they believe that you have been the victim of police misconduct.
Pitchess motions are only valid if you can show “good cause” to believe
- that the officer might have engaged in misconduct, and
- that the misconduct is relevant to your defense case.50
If the judge believes that you have demonstrated good cause as to why the sought information is material to the case, they will conduct an in-camera Pitchess hearing. An “in-camera” hearing is one that is private rather than conducted in open court like a suppression hearing.
Additional Reading
For more in-depth information, refer to these scholarly articles:
- Criminal Procedure: California Tells Criminal Defendants They Can No Longer Make Oral Motions to Suppress Evidence at the Preliminary Hearing – McGeorge Law Review
- Search Warrants, Motions to Suppress and Lost Cases: The Effects of the Exclusionary Rule in Seven Jurisdictions – Journal of Criminal Law and Criminology
- Exclusion of Evidence Obtained by Illegal Searches–A Comment on People v. Cahan – California Law Review
- Evidence: Motion to Suppress Evidence Obtained by Illegal Search and Seizure – California Law Review
- Inaccurate Search Warrant Affidavits as a Ground for Suppressing Evidence – Harvard Law Review.
Legal References:
- Penal Code 1538.5 PC.
- See same.
- See same.
- See same.
- See same.
- Our California criminal defense attorneys have local Los Angeles law offices in Beverly Hills, Burbank, Glendale, Lancaster, Long Beach, Los Angeles, Pasadena, Pomona, Torrance, Van Nuys, West Covina, and Whittier. We have additional law offices conveniently located throughout the state in Orange County, San Diego, Riverside, San Bernardino, Ventura, San Jose, Oakland, the San Francisco Bay area, and several nearby cities. Please contact us at Shouse Law Group with any questions.
- Penal Code 1538.5 PC – Motion to suppress evidence, endnote 1, above. See, for example, People v. Gonzales (2021) 12 Cal. 5th 367; People v. McDaniel (2021) 12 Cal. 5th 97.
- See same.
- United States Constitution, amend. IV.
- Cal. Const., Art. I, Sec. 13.
- See endnotes 9 and 10 above.
- Health and Safety Code 11350 HS – Drug possession
- Based on the facts of People v. Murray, (1978) 77 Cal.App.3d 305.
- See, for example, People v. James, (California Supreme Court, 1977) 19 Cal.3d 99, 106. (“Defendant first contends [in a motion to suppress] the evidence of the stolen television set in his house was obtained by an illegal search and seizure. Our guiding principles are well settled. (1) Inasmuch as the search herein was conducted without a warrant, the burden was on the People to establish justification under a recognized exception to the warrant requirement . . .”)
- See same. See also People v. Williams, (1999) 20 Cal.4th 119, 127. (“Here, of course, the search was without a warrant. Defendant notes that the prosecution has the burden of proving, if it can, some justification for a warrantless search or seizure [challenged by a suppression motion], and therefore a warrantless search is presumptively unreasonable.”)
- People v. Murray, supra at 310. (“While a search and seizure conducted pursuant to a warrant is presumed to be legal and the burden is on the defendant [who files a motion to suppress] to show the illegality . . . .”)
- See same. (“The People may discharge the foregoing burdens [during a California 1538.5 hearing] by a preponderance of the evidence.”)
- People v. Mabini (Court of Appeal of California, Second Appellate District, Division Six, 2001) 92 Cal. App. 4th 654.
- People v. Carter, (2005) 36 Cal.4th 1114, 1141. (“An illegal search or seizure violates the federal constitutional rights only of those who have a legitimate expectation of privacy in the invaded space or the seized thing. (United States v. Salvucci (1980) 448 U.S.83, 91-92 [100 S.Ct. 2547, 2553, 65 L.Ed.2d 619, 628].) The legitimate expectation of privacy must exist in the particular area searched or thing seized in order to bring a Fourth Amendment challenge [known in California as a Penal Code 1538.5 motion to suppress evidence].’ ( People v. Hernandez (1988) 199 Cal.App.3d 1182, 1189, 245 Cal.Rptr. 513, italics in original.)” (People v. McPeters, supra, 2 Cal.4th 1148.) The burden is on the defendant to establish that a legitimate expectation of privacy (Rawlings v. Kentucky (1980) 448 U.S. 98) was violated by government conduct.”)
- San Francisco criminal defense attorney Neil Shouse is an honors graduate of UC-Berkeley and Harvard Law School. He served for five years as a Deputy DA for Los Angeles County, prosecuting more than 60 criminal trials and earning a phenomenal 96% success rate in felony jury trials. Now, as the founding partner of Shouse Law Group, he represents criminal defendants in all stages of the trial and pretrial process, including crucial motions like motions to suppress evidence.
- People v. Parson, (2008) 44 Cal.4th 332, 345.
- See People v. Carter, endnote 19, above. (“To accept defendant’s assertion that he had a legitimate expectation of privacy while driving a stolen vehicle would be to overlook the word “unreasonable” in the Fourth Amendment’s proscription against “unreasonable searches and seizures.””)
- People v. Valdez, (2004) 32 Cal.4th 73, 122. ([With respect to a California Penal Code 1538.5 motion to suppress evidence,] “A passenger in a vehicle may not challenge the seizure of evidence from the vehicle if the passenger asserts “neither a property nor a possessory interest in the automobile nor an interest in the property seized.” (Rakas v. Illinois (1978) 439 U.S. 128, 148.) As a passenger, defendant lacked a reasonable expectation of privacy in the area under the driver’s side seat and thus cannot challenge the seizure of the gun. ( Id. at pp. 148-149, 99 S.Ct. 421.) The trial court therefore did not err in denying the motion to suppress.”)
- People v. Hughston, (2008) 168 Cal.App.4th 1062, 1070-71.
- In re Lisa G., (2004) 125 Cal.App.4th 801, 808. (“On the other hand, students in public schools have a legitimate expectation of privacy in the personal effects they bring to school.”)
- Based on People v. Parson, endnote 21, above.
- Wong Sun v. U.S., (1963) 371 U.S. 471, 484-485. (“The exclusionary prohibition extends as well to the indirect as the direct products of such invasions. Silverthorne Lumber Co. v. United States, 251 U.S. 385. Mr. Justice Holmes, speaking for the Court in that case, in holding that the Government might not make use of information obtained during an unlawful search to subpoena from the victims the very documents illegally viewed, . . . :”)
- Black’s Law Dictionary (9th ed. 2009), evidence: derivative evidence. (“Evidence that is discovered as a result of illegally obtained evidence and is therefore inadmissible [and may be excluded based on a motion to suppress] because of the primary taint.”)
- See same, fruit-of-the-poisonous-tree doctrine. (“The rule that evidence derived from an illegal search, arrest, or interrogation is inadmissible because the evidence (the “fruit”) was tainted by the illegality (the “poisonous tree”) [and thus may be suppressed through a motion to suppress]. Under this doctrine, for example, a murder weapon is inadmissible if the map showing its location and used to find it was seized during an illegal search.”)
- Loosely based on Silverthorne Lumber Co. v. U.S., (1920) 251 U.S. 385.
- See U. S. v. Ceccolini, (1978) 435 U.S. 268.
- See Wong Sun v. U.S., endnote 27, above.
- See People v. Superior Court (Tunch), (1978) 80 Cal.App.3d 665, 680-681.
- Penal Code 1538.5 PC — Motion to suppress evidence. (“(g) If the property or evidence relates to a misdemeanor complaint, the motion shall be made before trial and heard prior to trial at a special hearing relating to the validity of the search or seizure. If the property or evidence relates to a misdemeanor filed together with a felony, the procedure provided for a felony in this section and Sections 1238 and 1539 shall be applicable (h) If, prior to the trial of a felony or misdemeanor, opportunity for this motion did not exist or the defendant was not aware of the grounds for the motion, the defendant shall have the right to make this motion during the course of trial.”)
- See same.
- See same.
- Penal Code 1538.5 PC – Motion to suppress evidence, endnote 4, above.
- See same.
- See same.
- Jauregi v. Superior Court, (1999) 72 Cal.App.4th 931, 939. (“Evidence Code section 300, not mentioned by either party, reads in relevant part that “Except as otherwise provided by statute, this code applies in every action before … a … superior court [including suppression hearings covering motions to suppress]”)
- U.S. v. Matlock, (1974) 415 U.S. 164, 175. (“However that may be, certainly there should be no automatic rule against the reception of hearsay evidence in such proceedings [suppression hearings to decide motions to suppress], . . . .”)
- Penal Code 1538.5 PC – Motion to suppress evidence. (“(o) Within 30 days after a defendant’s motion is granted at a special hearing in a felony case, the people may file a petition for writ of mandate or prohibition in the court of appeal, seeking appellate review of the ruling regarding the search or seizure motion. If the trial of a criminal case is set for a date that is less than 30 days from the granting of a defendant’s motion at a special hearing in a felony case, the people, if they have not filed a petition and wish to preserve their right to file a petition, shall file in the superior court on or before the trial date or within 10 days after the special hearing, whichever occurs last, a notice of intention to file a petition and shall serve a copy of the notice upon the defendant.”)
- See same. (“(j) If the property or evidence relates to a felony offense initiated by complaint and the defendant’s motion for the return of the property or suppression of the evidence at the preliminary hearing is granted, and if the defendant is not held to answer at the preliminary hearing, the people may file a new complaint or seek an indictment after the preliminary hearing, and the ruling at the prior hearing shall not be binding in any subsequent proceeding, except as limited by subdivision (p). In the alternative, the people may move to reinstate the complaint, or those parts of the complaint for which the defendant was not held to answer, pursuant to Section 871.5.”)
- California Rules of Court Rule 8.853 – Time to appeal. (“(a) Normal time. A notice of appeal must be filed within 30 days after the rendition of the judgment or the making of the order being appealed.”)
- Pennsylvania Bd. of Probation and Parole v. Scott, (1998) 524 U.S. 357, 363. (“As such, the [exclusionary] rule does not “proscribe the introduction of illegally seized evidence in all proceedings or against all persons,” . . . but applies only in contexts “where its remedial objectives are thought most efficaciously served, . . . .”)
- See same at 363-64. (“For example, in United States v. Calandra, we held that the exclusionary rule does not apply to grand jury proceedings; . . . Finally, in INS v. Lopez–Mendoza, 468 U.S. 1032, 104 S.Ct. 3479, 82 L.Ed.2d 778 (1984), we refused to extend the exclusionary rule to civil deportation proceedings, . . . . We therefore hold that the federal exclusionary rule [barring evidence which has been suppressed through a 1538.5 motion] does not bar the introduction at parole revocation hearings of evidence seized in violation of parolees’ Fourth Amendment rights. . . . ”)
- Penal Code 995 PC — Grounds; motion to set aside; delay in final ruling [another pretrial motion like a motion to suppress].
- See same.
- See Evidence Code 1043 EC – Pitchess motions [another form of pretrial motion like a motion to suppress evidence].
- See same. (“(b) The motion shall include all of the following: . . . (3) Affidavits showing good cause for the discovery or disclosure sought, setting forth the materiality thereof to the subject matter involved in the pending litigation and stating upon reasonable belief that the governmental agency identified has the records or information from the records.”)