Common Police Mistakes in Criminal Investigations

The police play a significant role in criminal prosecutions through their investigations. However, they make several mistakes that your defense attorney can leverage to defend you. These mistakes occur when the officer fails to follow the standard procedure or is biased in the investigation. Police can make mistakes when conducting investigations and it can lead to exaggeration or prosecution of the wrong person. The San Diego Criminal Attorney has experience working with many police officers and knows the common mistakes they make during criminal investigations.

Overview of Criminal Investigations

Criminal investigations begin in different ways depending on the crime. For example, a DUI investigation is different from an investigation after a 911 call. A criminal investigation starts with:

• A police stop especially in traffic violations or a police chase
• A police statement by a witness or victim of a crime
• Police witnessing the crime as it happens

Regardless of how the investigation begins, a police officer has to follow standard procedures that apply for criminal investigations.

These procedures dictate how to mark a crime scene, collect and preserve evidence. However, police often make mistakes when investigating crimes, affecting the validity of the evidence against you.

Police mistakes are one failure of the criminal justice system, which leads to the prosecution of the wrong people. These mistakes are either intentional or accidental, but they have the same impact.

Some of these mistakes include:

1. Failure to Secure the Crime Scene

The crime scene consists of a lot of evidence pointing towards the offender. The police are trained in identifying the boundaries of a crime scene and the people who can access it.

Securing a crime scene prevents the introduction of outside materials that could interfere with the investigation. A well-secured crime scene will have few to no interference, ensuring it remains as the offender left it.

If the officer fails to secure a crime scene, they expose it to:

• Interference of evidence
• Introduction of new evidence such as hair, footprints, and fingerprints
• Removal of crucial evidence such as fingerprints of the offender – if an officer fails, carelessly touches surfaces of a crime scene, he or she might erase or smudge the prints of the offender

To prevent the occurrence of such problems, the investigators should:

• Locking down the crime scene which involves removing everyone from the crime scene
• Set up the parameters of the crime scene commonly done using a crime scene tape. The crime scene usually includes places the suspect has been at while committing the crime.
• Establishing a path of contamination, which controls the materials, introduced into the crime scene. The police officers are required to take note of areas the witnesses or other people within the crime scene hake passed or touched. Recording such interference enables investigators to eliminate changes made to the scene by people other than the offender.
• Securing the crime scene to prevent the entry of unauthorized persons, which will include keeping a log of people who enter or leave the crime scene

When investigators overlook these standards, then your lawyer can use the mistakes to challenge the validity of the evidence gathered from the crime scene.

2. Mistakes when Collecting Evidence

Evidence from a crime scene is crucial in identifying the offender, and the materials used in committing the crime. In some cases, patterns of other materials such as broken glass could indicate signs of struggle from the victim. The common sources of evidence include:

• Hair
• Blood
• Skin cells
• Fingerprints
• Foot, shoe and tire impressions
• Gunshot residue
• Fire accelerants
• Weapons
• Tools
• Drugs or chemicals on the crime scene

The police follow different techniques when gathering evidence. These techniques include taking photographs, collecting samples of the materials in the crime scene.

Once collected, the officer must package and secure the evidence to prevent contamination, damage, loss, and deterioration. He or she achieves this through:

• Packaging the evidence and samples in the appropriate materials to protect their integrity
• Keeping a chain of custody of the evidence
• Sealing and labeling the containers containing the evidence
• Documenting the location from which the officer collected the evidence

When the officer makes mistakes when collecting evidence, the likelihood of convicting an innocent person increases.

3. Problems with the Chain of Evidence

The chain of evidence shows the “path” evidence goes through since its discovery or collection to the time of presentation in court. The police officer has to demonstrate:

• How the evidence has been stored
• The people who have had access to the evidence
• The location of the evidence
• Where the evidence was collected
• Additional details about the evidence

The court will determine whether the records about the evidence match the photographs at the scene of the accident. Also, the evidence has to match what was used for the crime or taken from the crime scene.

If the police records indicate that the evidence included a serrated kitchen knife, but the material in custody is a butcher’s knife, then the chain of custody is broken. The evidence cannot be used in court.

Similarly, the prosecution has to prove that the evidence has owned one authorized agency. If the item changes possession, then the police must have a record of how it was handled, and why it changed ownership.

Most police officers make mistakes in maintaining the chain of evidence, which creates uncertainties about the legitimacy of the evidence. Some of these mistakes include:

• Failing to mark and identify the evidence following the stipulated procedure
• Failing to keep a clear record of the items taken as evidence
• Failure to record the areas from which the evidence was found
• Failure to describe the condition of the evidence at the time of collection
• Fails to prevent alteration of the evidence

If the police make these mistakes with evidence, your defense attorney will raise a motion to suppress the evidence. The court will then determine whether to exclude the evidence.

4. Failure to Read Miranda Rights

When investigating a suspect in custody, the officer has to read your Miranda rights. These rights inform you of your right to an attorney and the right to remain silent.

If you are read these rights and make an incriminating statement, the prosecution can use it as evidence against you in court.

Criminal defense attorneys often challenge any confessions made by the defendant if the officers did not read the Miranda rights.

In other cases, police often violate the Miranda rights of suspects. For example, an officer reads your Miranda rights but coerces you into confessing to committing the crime. The court will determine whether an investigating officer violates your Miranda rights using factors such as:

• How long the interrogation lasts
• The health, age, mental state and maturity of the suspect
• Whether the officer made promises of leniency
• Threats of physical harm
• Deprivation of food, use of the bathroom and water
• Torture
• Threats of bodily injury to another person
• Interrogation while under the influence of a drug or alcohol which affects your mental clarity
• Persistent questioning even after you insist on remaining silent

5. Searching Without a Warrant or Consent

The fourth amendment protects US citizens from illegal searches and seizures by requiring that officers search the property of another person with a warrant. A search is one that intrudes into your privacy in a place where you reasonably expect privacy. Such areas include your home or car.

If an officer suspects that you store illegal drugs in your home for trafficking, then they must get a search warrant for the house. If they do not get one, the evidence gathered will be unlawful. Also, the officer cannot use a search warrant for the house to search your vehicle.

Search warrants also apply to investigations such as taking photographs and eavesdropping on the suspect’s conversations. However, police do not need a permit for evidence that is in plain view or after the suspect gives consent.

Other situations that do not require a search warrant include:

• Emergencies which require the police to pursue an armed suspect or prevent injury to others
• After an arrest where police might search your person and your surroundings to check for dangerous weapons
• The police have towed or impounded your vehicle

Before getting a warrant, the officers have to prove that:

• They have probable cause to believe that a crime has occurred
• The evidence is likely in a specific location

Searches based on consent could also be illegal in situations such as:

• The police search your personal belongings after they get consent from your roommate
• A search based on the consent of your landlord

If you believe you might be the victim of an illegal search or seizure, talk to your defense attorney as soon as possible. Your attorney can review the circumstances to determine whether the police made mistakes when searching.

6. Use of Force

The law allows police officers to use reasonable force where necessary. However, some police take this too far by using excessive or unnecessary force.

Police brutality is a common problem that violates a person’s right from the excessive force, as stated in the fourth and eighth amendments.

Recently, California passed AB 392, which prohibits police officers from using deadly force unless necessary under the circumstances.

Previously, police could use deadly force, as long as it was reasonable. The measure of reasonableness depended on whether an officer in the same position would have used a similar force.

The bill targets to reduce police shootings and killings and increase accountability among officers. Police officers could shoot at a suspect is he or she reasonably believes that the person poses a risk to others.

The US Supreme Court has five gradual steps, which the police should follow in diluting a tense situation or arresting a suspect. These include:

• Using their physical presence
• Using verbal statements such as requests and direct orders
• Use of physical bodily force such as grabbing, punching or kicking
• Using less-lethal weapons such as Tasers
• Using lethal weapons such as firearms

Ideally, the police should start with the least force possible, depending on the circumstances. However, if a suspect shoots at the officer, the use of deadly force is reasonable.                                                       

If the police use excessive force during a criminal investigation, then the victim can file a civil lawsuit against the officer. During the trial, your attorney can prove that:

• The force originated from the officer
• The force was excessive compared to the resistance by the suspect
• The situation did not require immediate use of force
• The officer could have used less force with similar results
• The officer’s action was not reasonable or necessary

In addition to a civil lawsuit, police brutality can lead to criminal charges against the officer for battery, manslaughter, or murder. It could also lead to the reduction of your charges where applicable.

For example, if you are charged with resisting arrest, but it turns out that the officer used unnecessary force and you were not resisting, the charge could be dropped or dismissed.

7. Police Misconduct

The police can engage in unethical behavior that compromises the credibility of honest officers as well as the criminal justice system. Such misconduct leads to the arrest and conviction of innocent victims.

Police officers can engage in different forms of misconduct ranging from planting evidence to coercing witnesses to give false testimonies.

The number of arrests or closed cases an officer makes contributes to his or her performance reviews. Some of these officers resort to misconduct by planting evidence to facilitate an arrest or a conviction.

A police officer commits a crime when he or she knowingly introduces evidence into a crime scene to implicate another person. In some cases, the police collaborate with the offenders to create evidence that points away from the offender.

Police also engage in misconduct by coercing witnesses to give testimonies. This can happen during questioning when the officer gives a witness guiding statements. Such statements can lead to wrongful witness identification and the arrest of the wrong person. Another form of misconduct is coaching witnesses to frame the suspect.

In some cases, police officers file false information and fabricated evidence. Some police officers engage in the fabrication of evidence to cover up earlier errors in investigations or to effect a conviction.

An officer can also engage in misconduct by presenting false testimony in court. Law enforcement officials could lie in court to effect the conviction or cover up their errors.

Most criminal defense attorneys cite police misconduct either as a plea bargain to have the charges reduced or dismissed. In some cases, police misconduct is used as evidence during an appeal to overturn the ruling of a lower court.

8. Entrapment by Undercover Officers

Undercover officers often interact with criminals to help them identify criminal activities. Drug cases often involve busts by undercover police officers. The undercover officer is supposed to arrest offenders whom he or she notices committing the offense.

However, some officers, in their zeal to make an arrest, may coerce a person into committing the offense. For example, if an officer consistently pleads with an accountant to commit check fraud, even after the accountant’s refusal, the officer could be guilty of entrapment.

Most undercover officers operate by proving the suspect with an opportunity to commit the crime. When the defendant acts on the opportunity, then he or she is guilty of the crime.

If your defense attorney can prove that the officer coerced you into committing the crime, then the charges might be dropped. However, your attorney must prove that you would not have committed the offense under normal circumstances.

9. Failure to Document

Police often make several mistakes when writing their reports. The errors arise from misrepresentation of facts, falsifying reports, or omission of specific facts. Police make several types of errors when creating reports, including:

• Mistakes of facts such as wrong contact information or confusion about the color of clothes the suspect wore
• Mistakes of judgment
• Mistakes of law

In some cases, the police fail to document critical details about the offense. Officers are required to support their testimonies during court proceedings. They can use their field notes as well as the report to support the validity of their testimony.

Some of the information an officer should document includes:

• The date of the events
• The observations at the crime scene
• The contact information of witnesses
• The information provided by witnesses

Ideally, an officer should keep the notebook he or she used to record observations at the crime scene. He or she can then present this information to the court when required.

Find a San Diego Criminal Defense Attorney Near Me

Facing charges for an offense can be overwhelming for you and your loved ones. If the weight of the charges weighs you down, hire a criminal defense attorney to help you with your case. The attorney can identify weaknesses with your case and develop a strategy that exploits these strategies in your favor. The San Diego Criminal Attorney, through years of experience, knows the common mistakes that police make when investigating a crime. Therefore, our attorneys can apply this knowledge in your case, to identify mistakes the police have made. If you believe the police made a mistake when investigating a crime, call us at 619-880-5474.