Evidence Law and Admissibility

Crime Scene Investigation

• The good-faith exception doctrine allows evidence to be admissible in court even if the search warrant is later deemed invalid, as long as the officer executing the warrant believed it to be valid at the time.

Privileged Communication

• The Florida Evidence Code recognizes the importance of protecting certain privileged communications, such as those between a sexual assault counselor and victim, or a domestic violence advocate and victim.
• These communications are private, protected, and confidential, and their disclosure cannot be forced.

Securing and Protecting the Crime Scene

• The purpose of an investigation is to determine what happened, identify and locate the suspect, and develop enough evidence to establish probable cause to make an arrest.
• The preliminary investigation focuses on establishing whether a criminal act has been committed and, if so, what type and when and where it was committed.

Photographing Evidence

• Photograph evidence on a person before sketching the crime scene.
• Include the following information on a piece of paper or whiteboard and take a photograph:
  • Case number
  • Location
  • Date and time
  • Officer's name
• Indicate in the report that the photographs or sketches are true and accurate representations of the crime scene or person.

Sketching the Crime Scene

• Sketch the crime scene after photographing the scene and before beginning detailed work.
• A crime scene sketch supplements field notes and photographs, and aids in reconstruction, explanation, and permanent recording of an incident.
• Use sketches to document where evidence was recovered in the scene.
• Sketches can show positions of objects in relation to one another that are not easily visible in photographs.

Evidence-Handling Procedures

• Search for evidence using a systematic approach or pattern, depending on the type of crime committed.
• Use standard precautions and apply PPE when searching and handling evidence to avoid exposure to harmful substances.
• Follow agency policies and procedures for collecting, packaging, and preserving evidence.

Collecting Latent Prints

• Use a lifting tape to collect latent prints from a surface.
• Apply the tape carefully to avoid trapping foreign matter or air bubbles.
• Smooth out the tape from the tabbed end back toward the rolled end or vice versa.
• Lift the tape slowly, being careful not to touch the tape to another surface.
• Place the tape on the fingerprint card in the same way that it was placed over the print.
• Record the date, case number, location, and any other required information on the back of the fingerprint print card.

Elimination Prints

• Elimination prints allow fingerprint analysts to distinguish between prints belonging to victims and witnesses, or possible suspects.
• Take fingerprints from anyone who may have been at the crime scene to eliminate their prints from the pool of suspects.

Firearms Evidence

• When recovering a firearm or ammunition at a crime scene, follow agency policies and procedures for handling such evidence.
• Apply PPE to avoid contaminating the firearm or ammunition with fingerprints and DNA.

Chemical or Toxicological Evidence

• Identify various controlled substances and drug paraphernalia by sight or odor.
• Use a field test kit to test a substance before collecting and packaging it as evidence.
• Package sharp objects, such as needles or syringes, in puncture-proof packages clearly labeled with the words "WARNING: SHARPS."
• Follow agency policies and procedures for handling hazardous substances, such as fentanyl or carfentanil.

Fentanyl and Carfentanil

• Fentanyl and carfentanil are highly potent and hazardous substances that can be absorbed through mucous membranes.
• When encountering these substances, follow agency policies and procedures for field-testing, collecting, packaging, and transporting.
• Use PPE, such as gloves, long sleeves, a surgical or dust mask, and eye protection.
• Conduct field-testing in an open environment with no wind.
• Mark the package as "suspected fentanyl" and transport it with caution.
• If exposed to fentanyl or carfentanil, follow agency policies and procedures for decontamination.
• Signs of exposure include disorientation, difficulty speaking or walking, slowed pulse, nausea, slow shallow breathing, and respiratory arrest.

Test your knowledge of evidence law, including the good-faith exception doctrine and privileged communication. Learn how to ensure evidence admissibility in criminal investigations.