Part of Unit: Forensic Science
Lesson Plan Overview / Details
The most common form of fingerprints that have evidentiary value is latent prints. Latent prints are the result of moisture, oil, and other substances being transferred from a person's fingers to an object which occurs whenever you touch something. Recovering fingerprints from a crime scene typically involves the use of fingerprint powder and a brush. The composition of the powder depends on the manufacturer and type of powder. Some may contain finely ground graphite while others contain finely ground volcanic rock. They also come in a variety of colors, including fluorescent, to increase contrast with the background. In any case, the most important thing is that it is finely ground and very dry.
- Latent Print ID & Development
- 90 Minutes
California Career and Technical Education Standards
- PS.C.C1.2 Develop and maintain a constant awareness of potential problems.
- PS.C.C1.3 Process information effectively to make prompt and effective decisions.
- PS.C.C1.4 Use conflict-resolution and anger-management procedures to take charge of problems.
- PS.C.C1.5 Analyze and evaluate ideas, proposals, and solutions to problems.
- PS.FS.5.1 Apply appropriate problem-solving strategies and critical thinking skills to wor...
- PS.FS.5.2 Understand the universal, systematic problem-solving model that incorporates inp...
California Academic Content Standards (Reinforced)
- ELA.9-10.R.CAGT.2.5 Extend ideas presented in primary or secondary sources through original analysis...3
Objectives and Goals
- Students will identify and lift latent prints from smooth type surfaces.
- Students will identify and use latent print development equipment and instruments.
- Student will find matching fingerprints from sample rolled prints.
- Students will identify the materials and supplies needed to identify and lift fingerprints.
Activities in this Lesson
- Teacher Tube CSI Dusting Video - Hooks / Set
A demonstration by a forensic scientist of how to lift fingerprints at a crime scene.
- CSI Dusting Video [ Go to Site ] Teacher Tube Dusting For Prints Video
- Latent Print Identification - Projects
Latent - The skin has deposits of oil and perspiration that normally coat its surface. When the hand touches the surface, some of the moisture is transferred from the hand to the object, leaving an impression of the friction ridge detail. These are referred to as latent impressions.
On most surfaces latent impressions are not readily visible. The word latent is defined as not visible to the naked eye. That does not mean that it is actually invisible. On most surfaces, the impression will be revealed through the use of available or oblique lighting.
Students will be given equipment, objects to fingerprint and supplies to lift fingerprints. Teacher will provide hands on demonstrations of the techniques used to lift process and lift prints. Students will duplicate teachers work sample and produce usable prints.
- Latent Print Material & Equipment.doc [ Download ] Equipment & Materials · Black, Color Powder & Magnetic Powder· Brush for Black Powder· Brush for Color Powder· Brush for Magnetic Powder· White & Black fingerprint cards· Clear lifting tape (2 inch or 4 inch tape)· Glass Object
- Latent Print Lifting - Lab / Shop
- Students will wear protective gear, eye protective wear and latent gloves for health and safety requirements. Students will be given the supplies needed to get started. Teacher will give instructions and safety rules. Students will work independently and provide a work sample for teacher review.
- Students will put a small amount of powder in the top of the black powder container.
- Student will slightly dip brush in the top of the back powder container.
- Student will hold the object to be processed by the rim or inside the container rim. In some cases the student may hold the object from the bottom or the area where the container has no evidence.
- Students will slightly brush the container and when a pattern begins to develop, take the lifting tape and place it on top of the print. Slowly lift the tape and place the tape on a fingerprint card. Be sure to fill in the information on the fingerprint card.
- Assessment Types:
- Writing Samples, Demonstrations, Teacher-Made Test, Observations,
Teacher will observe students work and give positive feedback. Students will present work samples and receive feedback to improve and develop their skill levels.