In criminal cases, evidence can make or break a defense. It can mean the difference between a conviction and a dismissal. But what if vital evidence goes missing, is destroyed, or is never properly preserved? When this happens, the entire fairness of the case comes into question. In California, defendants have a legal tool called a Trombetta motion that may be used when the government fails to preserve potentially favorable evidence. This motion allows the defense to challenge the charges on the grounds that their constitutional rights to a fair trial have been compromised due to the loss or destruction of material evidence. Understanding what a Trombetta motion is, when it applies, and how courts analyze it can give defendants a powerful advantage in protecting their rights.
The Legal Duty to Preserve Evidence
Law enforcement agencies and prosecutors have a constitutional responsibility to preserve evidence that could be beneficial to a defendant. This duty arises under the Due Process Clause of the U.S. Constitution. If the government collects evidence during an investigation, it must take reasonable steps to maintain that evidence—especially if it might prove the defendant’s innocence or reduce their level of guilt.
When evidence is destroyed or lost, courts look at whether it was important to the defense and whether it could have changed the outcome of the case. If it could have, and the government is found to have acted improperly, the defendant may be entitled to relief.
What Is a Trombetta Motion?
A Trombetta motion is a legal request made by a criminal defendant asking the court to take action because the government failed to preserve evidence that might have been favorable. This could include physical objects, biological samples, surveillance footage, test results, or other materials that are no longer available by the time the case is being prosecuted.
These motions are named after a landmark Supreme Court case, California v. Trombetta, which established that the government has a duty to preserve evidence that has apparent value to the defense. If it fails in this duty, a defendant may claim that their constitutional right to a fair trial has been violated.
When filing a Trombetta motion, the defense is typically asking the court to either suppress certain prosecution evidence, dismiss the case entirely, or instruct the jury to consider the missing evidence as harmful to the prosecution’s case.
How Courts Evaluate Lost or Destroyed Evidence
California courts take a two-part approach when deciding whether lost or destroyed evidence warrants a remedy:
1. Was the Evidence Material and Favorable to the Defense?
The court considers whether the lost item had the potential to help the defendant’s case. It doesn’t need to be guaranteed proof of innocence, but it must have had apparent value. For example, if the evidence could have contradicted the prosecution’s claims or supported an alternative theory of events, it is likely to be seen as favorable.
2. Was the Government at Fault and Is the Defense Prejudiced?
Next, the court examines how and why the evidence was lost. If it was destroyed intentionally, or even recklessly, the court may view this as a serious violation. However, even if the loss was accidental, the court will still consider whether the defendant suffered harm as a result. If the loss of evidence makes it significantly harder for the defense to present its case, the court may grant relief.
In some cases, if the court finds that the police or prosecution acted in bad faith—meaning they intentionally destroyed or failed to preserve key evidence—it may lead to dismissal of the charges. But if the loss was due to negligence, the remedy might be limited to suppression of certain evidence or a special jury instruction.
Common Scenarios Where Trombetta Motions Arise
Trombetta motions are most commonly seen in cases where physical evidence is central to the defense. Here are a few examples:
-
DUI Cases: A common example is a DUI arrest where a breath test was conducted, but the breath sample wasn’t preserved, and the defendant wasn’t offered the opportunity to provide a blood or urine sample for independent testing.
-
Destroyed Surveillance Video: If security footage that could show the defendant’s location or actions at the time of an alleged crime is lost before trial, the defense may argue the case should be dismissed or evidence suppressed.
-
Lost Biological Evidence: DNA samples, fingerprints, or other forensic materials that were lost by crime labs or improperly stored can trigger Trombetta motions, especially if those items could have been tested to potentially exclude the defendant.
-
Deleted Police Body Cam Footage: If officers fail to retain body-worn camera recordings from key parts of an investigation or arrest, and those recordings could have supported the defendant’s version of events, a motion may be filed.
The Importance of a Trombetta Advisement in DUI Cases
In California DUI cases, officers are required to give what is known as a Trombetta advisement before administering an evidentiary breath test. This means they must inform the suspect that the breath testing machine does not retain a sample for later testing, and that the suspect has the right to request a blood or urine test, which can be preserved and independently analyzed later.
If this advisement is not given, and the defendant was not given the chance to request a retestable sample, the defense may argue that their rights were violated and ask the court to suppress the breath test results or even dismiss the charges in serious cases.
What Happens if a Trombetta Motion Is Granted?
If the court agrees that the destruction or loss of evidence violated the defendant’s rights, several outcomes are possible:
-
Suppression of Evidence: The court may prohibit the prosecution from using certain evidence or testimony that relied on or was connected to the lost item.
-
Favorable Jury Instruction: The judge may instruct the jury that they can consider the missing evidence as something that would have helped the defense, potentially raising doubt about the prosecution’s case.
-
Case Dismissal: In rare but severe cases, especially where the government acted in bad faith and the missing evidence was critical, the court may dismiss the charges entirely.
What Defendants Should Do if Evidence Is Missing
If you or someone you know is facing criminal charges and you suspect that evidence was lost, destroyed, or never properly preserved, it’s essential to act quickly. A skilled defense attorney can:
-
Investigate the chain of custody and determine when and how the evidence went missing
-
Gather records, reports, and witness statements to understand what happened
-
File the appropriate motions with the court to challenge the fairness of the case
-
Argue for suppression, dismissal, or other remedies to protect your rights
Time is critical. The sooner a defense team begins working to address the issue, the more likely it is that meaningful relief can be obtained.
Limitations of Trombetta Motions
While Trombetta motions are powerful, they’re not guaranteed to succeed in every case. Courts are generally reluctant to dismiss criminal charges unless there is clear evidence of wrongdoing or serious prejudice to the defense. The burden is on the defendant to prove that the evidence was valuable, that it could not be duplicated, and that the loss undermines the fairness of the trial.
Even if the government acted negligently, the court may only provide limited remedies unless it can be shown that the evidence was crucial to the defense. Still, pursuing a Trombetta motion can often lead to important strategic advantages or favorable outcomes in plea negotiations.
Conclusion
The loss or destruction of evidence in a criminal case can have serious consequences for the accused. When key evidence is no longer available, and it could have helped the defense, the fairness of the entire process comes into question. A Trombetta motion offers defendants in California a vital legal pathway to challenge the prosecution and demand accountability for mishandled or missing evidence.
Whether you’re facing DUI charges, theft, assault, or any other criminal allegation, knowing your rights and acting quickly can make all the difference. If you believe important evidence has been lost in your case—or you’re not sure—don’t wait.
Call to Action
If you’re facing criminal charges and suspect that key evidence has been lost or mishandled, Southwest Legal is ready to help. Our experienced criminal defense attorneys understand the complexities of Trombetta motions and how to use them to your advantage. We fight to protect your rights and ensure you get the fair trial you deserve. Contact us today for a free consultation and let us evaluate your case. Don’t let lost evidence stand in the way of your future.
