Lifting Prints from Wet Surfaces
Fingerprints will remain intact on wet surfaces. You have two options for developing and lifting latent fingerprints from them.
Chain of Custody of a Body Begins with the Death Scene Documentation
When working on a death scene, keep track of how and when the coroner was notified of the death. When the body is ready to be moved, continue to jot in your checklist, everything that happens. These notes begin the documentation of the chain of custody of the body.
Respond with Caution
Officers who arrive at a crime scene must be cautious and methodical. They should strive to preserve the scene with minimal contamination and should not disturb physical evidence.
Essential Items for Crime Scene Personnel
Responding crime scene officer(s) must have the following items readily available. Officers should keep them in police vehicles or readily available toolkits.
Transportation and Storage of DNA Evidence
Direct sunlight and warmer conditions may degrade DNA, thus officers should avoid storing or transporting this evidence in places that may get hot, such as the trunk of the police car.
Crime Scene Integrity
Protection of the crime scene is essential to the protection of evidence. Safeguarding and preserving evidence is fundamental to the successful solution of a crime.
Identifying DNA Evidence
Since only a few cells can be sufficient to obtain useful DNA information to help your case, the list below identifies some common items of evidence that you may need to collect.
Casting Materials can be Used to Obtain Fingerprint Evidence
Hard to lift prints, such as those on rough surfaces, human skin, blood, and curved surfaces can be accomplished by using magnetic powder and casting silicone.
It's Important to Consider Whether to Leave a Cell Phone On or Off when Collecting it into Evidence
During the collection of cellular phones, there has been a debate on how to best preserve their data. This debate centers on whether to turn the phone off or leave it on at collection.
Gang Members Use Social Media
In their online chat sessions, gang members discuss activities that include the planning and execution of crimes, drug cultivation and distribution, and the buying and selling of weapons.
How to Collect Internet Evidence
The courts have generally accepted evidence collected from the Internet as long as its authenticity can be established. Commonly accepted digital forensic methodologies can all be used to identify a three-pronged approach to Internet forensics.
Use a Checklist to Document a Crime Scene
Using a checklist to document a crime scene is your reminder to look at everything; insurance that even if you get distracted, you will go back; and a record that you looked for each type of evidence even if none was present.
Fingerprint Brushes can Contaminate DNA Evidence
Fingerprint brushes can become easily contaminated. New brushes should be used for each crime scene, and the brush used in a homicide case should become part of the evidence.
Questioned Documents
Through visual examination or advanced chemical analysis of inks and paper, forensic investigators can determine information relating to a questioned document's authentication, authorship or creation date.
Processing a Fire or Arson Scene
The investigator should control access to a fire scene after fire suppression and see that evidence is collected, stored, and transported so that it will not be contaminated. Follow this walkthrough to properly process the scene.
Control Contamination
The investigators in charge of a crime scene should create an investigation team and process the scene carefully and methodically to protect the evidence. Follow these steps to control contamination and cross-contamination and to ensure scene safety and evidence integrity.
8 Common Misconceptions Plague Bone and Tool Mark Trauma Analysis
Saw mark research is focused on collecting data on variation found in microscopic features of cut bone. The narrowing of the field of possible tools that could have potentially been used in a crime makes saw mark characteristics a valuable tool for the forensic examiner. Unfortunately, a standard methodology for saw mark analysis is lacking, and the field is hindered by numerous misconceptions.
Train Your Field Officers
Remember that working a crime scene should be a team effort for you and your department. One of the best things you can do is train the field officers and the first responders about your capabilities.
The Scene Will Dictate What You Need From the Suspect
Our primary job as crime scene investigators is always the same: to tie a suspect to the scene. The way to accomplish this goal is to collect as much evidence as possible from the scene and the suspect.
Proper Note Taking is Essential in Documenting Bloodstain Patterns
The fundamental goal of documenting bloodstain patterns is to accurately depict the patterns as you found them. Your notes should contain a detailed description of the physical characteristics of the patterns including size, distribution, location, shape, and physical features.
Use Photography to Create an Accurate Record
When photographing a scene, keep in mind that you are trying to provide a permanent record of the scene and the evidence collected. This record will assist anyone who is not at the scene—from detectives and prosecutors to members of the jury, if the case goes to trial.
Forensic Archeology Helps Dig Up Evidence
Forensic archeological investigations are integral to a diverse array of situational contexts, but the singular objective these various operations accomplish is one of recovery and resolution—recovery of the physical evidence and eventual resolution of the legal issues.
Executing a Warrant for Digital Evidence
Pertaining to the seizure of digital devices, there is some misunderstanding concerning what “executing the warrant within ten days” actually means. Often, investigators will detail what types of computer files they are going to be looking for so as not to run afoul of the Fourth Amendment.
Develop a System for Marking Evidence
No matter the type of scene, you must carefully mark and record every piece of evidence you find. This may seem pretty straightforward, but it becomes more complicated when you have multiple crime scenes or incidents. Taking the time to develop a clear system that is easy to use will be well worth the effort.
Properly Package DNA Evidence
Once you have identified DNA evidence, you need to properly collect it and package it. Remember that DNA can be easily contaminated or damaged.
