Wednesday 1 June 2016

Forensic Crime Scene Techniques: A Must Know For Nigerian Lawyers Judges And Law Enforcement Agents

                                             
                 

“We have problem resolving serious crime because many a time, Nigerians tamper with key evidences in crime scenes..
” This was the FCT's Commissioner of Police, Wilson Inalegu speaking to Premium Times back  in March 2015.
In March this year, Canadian police officials delivered a week-long training  to Nigerian Police investigators on how to improve their capacity for major case and crime-scene management, evidence collection and preservation.
That is a great step in the right direction!

 Forensic  science begins at the crime scene. The risk of contaminating evidence at a crime scene can be reduced by 97% if the law enforcement officers, the public and forensic experts understand and  apply the principles of  crime scene management.
Processing a crime  scene (which involves preserving the crime scene in its original state, search,recovery and proper packaging of physical evidence) is considered  to  be  one  of the most critical aspects of effective criminal investigations.

An improperly managed crime scene will always produce contaminated and poor quality evidence. When lawyers and prosecutors  use such evidence, it increases the  risk  of ineffective investigations. The result is unavoidable:  wrongful  convictions and acquittals. The innocent is  thrown to prison while the guilty walks... as free as air!

Nigerians will have pride, if the Nigerian police begins to apply forensic principles to everyday investigation! How explosive that will be on crime fighting! Imagine the look on the face of someone accused of killing his wife when confronted with tangible evidence that he cannot deny.... evidence that solidly rests upon the unshakable laws of science! Nigerians will begin to trust in the system and believe that the system can provide true justice...justice that they can trust!
This article therefore, hinges on the need for law enforcement agents (especially the police) to follow a systematic forensic approach to crime scene processing.....crime scene processing steps that will produce quality, uncontaminated evidence that can be admissible in court without fear of presenting compromised evidence which may later backfire when the truth is revealed.
The following steps are basic crime scene principles that everyone involved at a crime scene must understand and dutifully apply.

    Protecting the crime scene
Nothing should be added to or removed from a scene of crime. The first police officer(s) or other law enforcement agents should do all they can to preserve the integrity of the crime scene.
Wearing of clinical latex gloves, not moving the body of victim if dead, not stepping on blood spatter, even covering the body of a dead victim should be avoided because you can alter, destroy or contaminate evidence that might prove crucial to apprehending the perpetrator(s) of the crime!

In Nigeria, it is a common practice to cover dead bodies even before the experts come to examine and collect evidence (the ethics behind that practice is  controversial though).  It is important for you as a law enforcement officer or concerned citizen to note that if you arrive at a crime scene and a victim show signs of life, then do all you can to save the life of that person(and try as close as possible to minimize contaminating any thing you think is of evidential value). The more reason why more personnel need to have basic training on lifesaving techniques.

Limiting access only  to major investigating officers and forensic experts will increase the chances of recovering evidences that are of high quality. That is why the customary yellow tape with "'do not cross', crime scene authorised personnel only' " is very essential. No one should be allowed access into the restricted area except he or she has a definite task to accomplish that is directly part of the investigation...not even politicians! The investigating officers and the forensic guys should be allowed to do their job without external interference.

Sometime in early 2015,  armed robbers attacked the home of the former Chief Justice of Nigeria, Mohammed Uwais, the then FCT police boss mentioned that before forensic experts arrived to study the crime scene, workmen who were working on inverters in the compound had already tampered with key evidences..."without knowing the implications.
A crime scene manager is normally appointed present to oversee all activities and controls access to the victim(s) at the crime scene. Therefore, there is need for law enforcement and emergency jurisdictions  (such as the Nigerian Police, DSS, Nigerian Army, Navy, Airforce, NDLEA, Civil Defense) to agree to a plan on who is in charge at crime scenes to avoid unnecessary and costly frictions among their participating personnel. Also, that person should be grounded in basic crime management principles and know which forensic expert(s) to invite on a case-by-case basis.

  Proper recording of the crime scene.
At the crime scene, the processing team need to have a photographer with a high definition (HD) camera that will take high quality long, short and medium range photos including videos.
The officers in charge and experts are expected to make sketches and notes of whatever they do and occurs. They can be called to court to give their own version of what happened then they will have to fallback to these notes. Some crime scene investigators and experts record audio/video on phones so as not to leave anything out. A lawyer, prosecuting or defense will find these resources invaluable and vital to proving your case in court.
Important notice
Nothing is not important at a crime scene.

  Chain-of-custody Of Forensic Evidence
Before any material evidence is recovered and packaged, a book should be provided for that will contain every transfer of evidence, who collected what and to whom did he or she hand that evidence to, time, date and signature among others.
There was a case in the United States where the prosecution's evidence was discredited because the names of the police officers and forensic experts who handled and analysed the forensic evidence were not recorded  on the 'log book'.

Remember the OJ Simpson case in the 90s? Mr Simpson was allowed to walk free because a police officer whose duty it was to transport the DNA evidence obtained from the crime scene, 'branched home' before arriving the station. Was there not a chance that  the blood sample could have been switched? 

Law enforcement officers at crime scenes need to have this book on ground. It is called a chain-of-custody book.
The importance of maintaining an effective chain-of-custody system by Nigerian crime scene officers cannot be over emphasized. It ensures that integrity of the evidence that forensic experts, lawyers and judges will use to prove or disprove the innocence or guilt and the ultimate acquittance or conviction of a suspect.

  Search And Recovery Of Physical Evidence.
This is the most sensitive of all steps. After you have succeeded in preserving the crime scene, taken appropriate records and your chain-of-custody system is in place...the next thing is to begin the search for anything that you think is related to the crime committed, important or not!
Here, you need intuition and all your 'forensic senses' at their peaks. Of course you should be wearing latex gloves by now...in fact, since your arrival. Recovery of evidence will require you looking for both big, small or minute materials also known as trace evidence. 

Tiny strands of hair, a tiny droplet of blood, a cut finger or toe nail, dusting doorknobs, tables, handles for fingerprints. A forensic entomologist will be searching for flies, maggots or tiny eggs.... it's endless! --even used tissue papers in the dustbin can unlock a clue to the case!
Is this a job for untrained persons? Our officers need training!

  Forensic evidence search and recovery requires painstaking efforts and patience. The gains of a well searched crime scene are really worth the efforts and costs invested.
A colleague of mine once lamented that on arrival at a burglary theft scene, the officers involved in the investigation were already having a 'field day', touching anything touchable and 'marching' anything march-able--- without latex hand gloves. Your guess is as good as mine. He could not do much because every conceivable material that was supposed to be processed and become relevant to the case lost its forensic value!

  Evidence Packaging And Labelling
Proper packaging of the evidence recovered is vital to ensure that materials of evidential value such as strands of hair  does not go missing,  the fingerprints impression does not get distorted, the urine or blood sample does not degrade or mix with other fluids. Proper packaging ensures that clothes of victims and suspects are stored in the same paperback or containers.

This will involve putting dried DNA blood evidence in little paper envelopes, collecting fire accelerants such as petrol in metallic cans and not jerrycans, storing clothes of victims and suspects in air tight and water proof cellophane bags- with proper labelling.

6. Evidence Storage And Analysis
Properly packaged material evidences are transported from the crime scene to forensic laboratories where the scientist or technologist analyses those evidence. For instance, a blood sample will be sent to the forensic geneticist who will process it for DNA evidence. His assignment will be to determine whose DNA is it? And possibly link the owner of that DNA sample to the crime scene or victim.
In most cases, the blood sample is kept cool in refrigerator until when it is needed. The storage facility differ for various material evidence.

Dried bloodstain  cards, fingernails, hair and other  trace  evidence should be stored at room temperature (20°C). Biological samples such as oral, vaginal, anal, penile, and  bladder  swabs should be stored in the refrigerator at 4°C. This can preserve the evidence for many months until they are retrieved for analysis.

In all of this, whoever handles the packaged material evidence fills the log book and must indicate the time, date and for what purpose. This is very important. Smart lawyers will quickly make the judge realise anybody could have tampered with the evidence since there was no record to show the chain of custody- thus casting doubt on the integrity of the forensic evidence. You know things didn't go your way when you hear that emphatically spoken statement of victory...."that will be all my lord". That would be bad....after all your hard work! 

All policemen and women need to firmly grasp these principles of crime scene management for quick and effective expedition of justice. Nigerian lawyers and judges need to have the proper understanding of the step-by-step process of forensic evidence from the crime scene to the lab and to the court.
The integrity of forensic evidence begins from the crime scene. If we can't achieve that, what will be the fate of the innocent and guilty? Justice denied or Justice delayed?

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