How Police Mistakes and Misconduct Can Lead to Wrongful Arrests

Like people in any other job, police officers sometimes make mistakes. Other times, they make decisions that seem rational but can have disastrous consequences for a suspect. Worst of all, some officers abuse their position by intentionally engaging in conduct that taints the investigation.  

Sadly, research shows that police mistakes and misconduct play a role in far too many criminal cases. This article outlines several types of police mistakes and misconduct that might lead to a wrongful arrest. It also explains how a Marin County defense attorney can help you or your loved one fight back against negligent or intentional police conduct in your case. 

Why Police Mistakes Can Result in Wrongful Arrests

Before addressing the different types of police mistakes and misconduct, it’s helpful to understand exactly why police actions matter so much in criminal cases. 

A typical police investigation starts with a complaint or 911 call. Then, the police start collecting evidence and talking to witnesses. At some point, they will identify potential suspects. They may interview one or more of the suspects. Finally, the police will need to ask a judge for an arrest warrant. 

The California Penal Code says that a judge can issue a warrant if the officers provide “probable cause.” The U.S. Supreme Court has said that probable cause exists where “there is a fair probability that contraband or evidence of a crime will be found in a particular place.” However, the standard of “a fair probability” is quite low. When a classic study asked federal judges to assign a number to probable cause, the average response was 44.5 percent certainty. Meanwhile, most experts place the “beyond a reasonable doubt” standard at well over 90 percent certainty. 

Because the probable cause standard is so low, mistakes and misconduct during the investigation stage can change the course of the case. For example, the issues with eyewitness testimony are well known. If a police officer blindly accepts an eyewitness’s account, the wrong person could lead to a wrongful arrest. 

Police Mistakes: Examples and Why They Happen 

Being a police officer is a highly stressful job. When the pressure of the job is combined with large caseloads, communication and recordkeeping failures when cases are passed between officers and departments, and other issues, it’s easy to see how mistakes can happen. The overwhelm can lead to mistakes, including: 

• Labeling evidence improperly
• Failure to maintain a proper chain of custody for evidence 
• Lost or misplaced evidence 
• Incorrect data entry 

Additionally, sometimes the fault is not the officer’s. Police often use technology in their work. When these tools don’t function properly, they can produce unreliable results. 

Investigative Biases: When Assumptions Replace Objectivity

Officers often feel pressure to make arrests quickly, especially in high-profile cases. Sometimes, these demands push officers to make assumptions rather than fully investigating. Additionally, this situation allows confirmation bias to flourish. Confirmation bias occurs when an investigator only focuses on the things that confirm what they already believe. While all humans experience confirmation bias to a degree, when police officers don’t look at every piece of evidence, innocent people may suffer. 

Here are a few examples of how investigative biases can affect police investigations:

Tunnel Vision

Tunnel vision is a specific type of confirmation bias. In tunnel vision, some piece of evidence or maybe even a “hunch” leads the police to believe that a particular person is guilty. As the investigation progresses, the officers no longer proceed as if they are trying to solve the case. Rather, they are looking for evidence that confirms their belief that their chosen suspect is guilty. While this may not sound like a big deal, when officers engage in this behavior, they overlook evidence that could prove their target suspect’s innocence. They may also ignore alternative explanations for evidence that could prove them wrong. Worst of all, they may stop investigating before interviewing certain witnesses or looking into other suspects. 

Trusting Eyewitnesses 

Police officers often rely on eyewitnesses. However, decades of research show that there are many problems with eyewitness identification. Witnessing a crime is a stressful event. In addition to the stress, the witness is expected to remember crucial details about someone that they’ve never met and perhaps saw for only a few seconds. As such, a witness’s memory may not be 100% reliable. 

Despite this, many officers continue to rely heavily on eyewitness testimony. The Innocence Project reports that nearly two-thirds of its wrongful conviction cases involve faulty eyewitness testimony. 

Suggestive Witness Questioning 

Most people think that our memories are like rocks – firm, fixed, and hard to change. Yet research shows that human memory is much more like Play-Doh – soft and easy to manipulate. In a criminal investigation, police officers must tread carefully to ensure that they don’t guide witnesses to a particular conclusion. For example, asking, “What do you remember about that night?” is very different than asking, “So, when did you see the green car?” Even if the witness had no memory of a green vehicle, the suggestion of the question can make them feel like they should.

Police Misconduct: When Officers Break the Rules

While the issues we’ve discussed so far involve innocent or at least somewhat reasonable behavior, some officers intentionally violate police rules, state law, and even constitutional rights during their investigations. Examples of this behavior include: 

• Hiding or destroying evidence that could prove a suspect’s innocence (exculpatory evidence)
• Using coercive or illegal tactics during interrogations
• Intentionally including false statements in official police reports 
• Tampering with evidence 
• Planting evidence 

The Innocence Project reports that police misconduct is a factor in nearly 40 percent of wrongful convictions. 

How a Marin County Criminal Defense Attorney Can Expose Police Mistakes and Misconduct 

Police officers are not perfect. Fortunately, our legal system allows the defendant and their attorney to challenge the police investigation. An experienced Marin County defense attorney can help you fight back against police mistakes and misconduct by: 

• Conducting a thorough investigation to find overlooked or hidden evidence
• Reviewing police reports, paperwork, and other records (e.g., dashcam and bodycam footage) for inconsistencies and omissions
• Challenging eyewitness identifications
• Proving that the investigators ignored other suspects
• Showing that confessions were illegally obtained 

Depending on the error in question, the attorney might also file a motion to suppress the evidence at trial or work to get the charges dismissed or reduced. 

If you’ve been charged with a crime in San Francisco or Marin County and need legal representation, contact Brownstein Law Group. The government has powerful lawyers on their side. You deserve the same. We’ll fight aggressively to protect your rights. Call 415-795-9059 or use our online contact form today to schedule a visit with our team.