WEDNESDAY SEPTEMBER 1ST, 2010

Agenda and Lecture Notes

Agenda for 1 Sept 2010

Roll Call Pledge (Weather Permitting) Current Events Birthday List!!! AM session only Discussion-JonBenet Ramsey: Who did it? Lecture: Physical Evidence and the

Crime Scene

Vocabulary/Spelling word of the Day Reminder: Tomorrow is PANTS day, bring money if

you want to purchase through the uniform company. ~ $38.00 cash or credit card. NO checks.

JonBenet Ramsey: Who did it?

Discussion: What mistakes were made during the initial response to the scene as well as during the subsequent investigation?

How did these mistakes sabotage any chances of JonBenet’s killer ever being brought to justice?

JonBenet Ramsey –A Sad Tragedy

JonBenet Ramsey –A Sad Tragedy

JonBenet Ramsey –A Sad Tragedy

Physical Evidence and the Crime Scene –Chapter 2

As automobiles run on gasoline, crime laboratories run on PHYSICAL EVIDENCE. Physical evidence encompasses any and all objects that can establish that a crime has or has not been committed or can link a crime and its victim or its perpetrator.

If physical evidence is to be used effectively, its presence first must be recognized at the crime scene.

Physical Evidence

Physical evidence achieves its optimum value in criminal investigations only when its collection is performed with a selectivity governed by the collector’s thorough knowledge of the crime laboratory’s techniques, capabilities, and limitations.

Investigators must use both knowledge and discretion in collection of evidence – if every natural and man-made object were collected from a scene, the enormous amount of material would immobilize a crime laboratory.

Physical Evidence and the Crime Scene

Thorough and competent investigations conducted by professional police officers when partnered with the crime lab’s capabilities will enhance the chances for a successful criminal investigation.

Forensic science is, and will continue to be, an important element of the total investigative process, but it is only one aspect of an endeavor that must be a team effort. The investigator who believes the crime laboratory to be a solution for carelessness or ineptness is in for a rude awakening.

Physical Evidence and the Crime Scene

Forensic Science begins at the crime scene. If the investigator cannot recognize physical evidence or cannot properly preserve it for laboratory examination, no amount of sophisticated laboratory instrumentation or technical expertise can salvage the situation. Not all crime scenes require retrieval of physical evidence, but once the commitment is made to process a crime scene for physical evidence, certain fundamental practices must be followed.

Preserving and Recording the Crime Scene

In order to be useful to investigators, evidence at a crime scene must be preserved and recorded in its original condition as much as possible. Failure to protect a crime scene properly or record its details accurately may result in the destruction or alteration of evidence, or hinder the search for the perpetrator by misleading investigators about the facts of the incident.

Secure and Isolate the Crime Scene

The first officer arriving on the scene of a crime must preserve and protect the area as much as possible. Of course, priority should be given to obtaining medical assistance for individuals in need of it and to arresting the perpetrator. As soon as possible, extensive efforts must be made to exclude all unauthorized personnel from the scene. As additional officers arrive, measures are immediately taken to isolate and protect the scene.

Secure and Isolate the Crime Scene

Ropes or barricades along with strategic positioning of guards will prevent unauthorized access to the area.

Determine the crime scene boundaries. This can be established after determining the perpetrator’s path of entry and exit.

The obvious items of crime scene evidence must be documented and photographed before the initial walk through.

After the obvious evidence has been documented, then a walk-through of the scene to gain a better overview of the situation can be performed. Only KEY personnel should be included in the walk through.

During the walk through a strategy for systematically examining and documenting the entire crime scene can be devoloped, while preserving the integrity of the evidence.

Record the Scene

Photograph – The most important prerequisite for photographing a crime scene is that it be unaltered.

THE GOLDEN RULE: Do not touch, move or alter any evidentiary item until you document the scene!

Record the Scene

Photography – Unless injured people are involved, objects must not be moved until they have been photographed from all necessary angles. If objects are removed, positions changed, or items added*, the photographs may not be admissible as evidence at a trial.

* (There will be times when things ARE added to a scene, for example, things left behind by the ambulance crew.)

Record the Scene

If evidence has been removed or moved before photographing, the fact should be noted in the report, but the evidence should NOT be reintroduced into the scene in order to take photographs.

A general rule to remember is that you cannot take too many photographs. Photographs that are not necessary simply will not be used. Sometimes certain photographs are taken simply to jog the investigators memory later when they are writing their report.

Record the Scene

Each crime scene should be photographed as completely as possible.

Photographs should be taken of the area immediately surrounding the crime scene and also of adjacent areas. This is where important acts occurred immediately before and after the commission of the crime.

Overview photographs of the entire scene and points of entry and exit must be taken from various angles.

If the crime occurred in a house, photographs of every room must be taken in a similar fashion.

Record the Scene

If the crime scene includes a dead body, photographs must be taken to show it’s position and location relative to the entire scene.

Close up photographs of injuries and weapons lying near the body are extremely important. Although photographs will be taken of the body by the coroner’s office, it is crucial that photographs be taken of the injuries while the body is still at the scene. However, do NOT move the body in order to take photographs of injuries! The body should not be moved by ANYBODY except investigators from the coroner’s office!

Record the Scene

After the body is removed from the scene, the surface underneath the body should be photographed.

As items of physical evidence are discovered, they are photographed to show their position and location relative to the entire scene. After these overviews are taken, close-ups should be taken from several distances to record the details of the object itself.

If the size of an item is significant, such as a bullet hole, a ruler or other measuring scale may be inserted near the object and included in the photograph as a point of reference. Be sure that the rule that you use can be submitted as evidence!

Record the Scene

Videotaping: The same methods should be used for videotaping that are used for still photography.

Crime Scene SketchesOnce photographs have been taken, the crime

CSI must sketch the scene. The first sketch, the one done while at the scene, is the rough sketch. The rough sketch must contain an accurate depiction of the dimensions of the scene and show the location of all objects having a bearing on the case.

Record the Scene

Objects are located in the sketch by distance measurements from two fixed points.

Each item in the sketch should be identified with a number or a letter.

A legend should correlate the letter to the items description.

Every sketch should include a compass heading designating north.

Record the Scene

The Finished Sketch The finished sketch is completed with care

and concern for aesthetic appearance.

The finished sketch must include and reflect all information contained within the rough sketch in order to be admissible in court.

Record the Scene

Rough-sketch diagram of a crime scene. Courtesy Sirchie Finger Print Laboratories, Inc., Youngsville, N.C., www.sirchie.com.

Record the Scene

Finished-sketch diagram of a crime scene. Courtesy Sirchie Finger Print Laboratories, Inc., Youngsville, N.C., www.sirchie.com.

Record the Scene

Finished sketch completed with computer aided drafting (CAD) software.

Record the Scene

A diagram completed with 3-D software.

Record the Scene

Notes Note taking must be a constant activity throughout the processing of the crime scene.

The notes may be the only source of information to refresh memory. The notes must be sufficiently detailed to meet this need.

Tape-recording notes at a scene can be advantageous – detailed notes can be taped much faster than they can be written.

Quick Review

Physical Evidence includes any and all objects that can establish that a crime has been committed or can link the crime and its victim or perpetrator.

Forensic Science begins at the crime scene, where investigators must recognize and properly preserve evidence for laboratory examination.

The first officer to arrive must secure the crime scene.

Investigators record the crime scene by using photographs, sketches, and notes and make preliminary examination of the scene as the perpetrator left it.

Spelling/Vocabulary Word of the Day

Rigor Mortis

Richard Safferstein, Copyright © 2011 Pearson Education, Inc., publishing as Pearson Prentice Hall, Upper Saddle River, New Jersey 07458.

Notes from this power point are from Chapter 2 in the textbook.