Reflective writing on our lecture (Science on focus special)

The lecture started with attractive demonstration in which the audience watched a live performance of the crime scene. The murder shot the professor and stole a CD from her computer.

Here is a brief summary of the logical investigation and analysis starting from the crime scene and ending with the criminal arrest.

First of all every crime has a history which means that the crime scene should not be changed until police collect all the evidence e.g. Finger print ,hair, foot print and body fluids.

They collect fingerprints from the surfaces which might be difficult in case the fingerprints are invisible and they treat them chemically (cyanoacrylate), and then they focus Laser light or ultraviolet on sample to spot them. These data are stored on the database in order to be compared with those for previous known criminals.


What might happen if the criminal was wearing gloves? Is it the end of the case?
Of course not, DNA is another effective technique which is very accurate because the percentage to find two genetically identical persons is 1 in 60 million (not twin).the investigators gather any biological materials that might be left behind the murder e.g., Hair , dandruff ,skin debris .Here the forensic scientists work on the nanogram scale so they treat this sample to dissolve protein and leave DNA which is the nucleic acid that carries our unique genetic map in form of the nucleotides bases (A,T,C and G) then they separate the sample by electrophoresis .and finally they feed this information into the computers.
This information can tell us if the murder was male or female as their chromosomes are XY and XX respectively but they did not give us general description for the murder .e.g. if he/she has blond hair or blue eyes.
On the other hand, they are very useful in case they were identical with someone's DNA profiling on the database. And also the biological material could supply investigators with some information about the murder habits .If he takes certain drug.


Moving on to the electrostatic Lifting operator technique that depends on the static electricity which means the electrons transfer from material to another this approach is used to identify the footprint (what kind of shoes the criminal was wearing) .

Gunshot residue which remains on the murder clothes is another tool for the investigation.
Video identification procedure: in this method specialists analyze the face into data by measuring the distances between eye, nose and ear and compare them with those on the national database (Evomorph).


Autopsy (Post mortem) report of 40 years old professor stated that her life is taken out due to two bullets, one of them settled in her heart.



The force linked intelligence system that pieces the evidence together through the computer .it is very powerful approach that connects the current crime with events that collected so far about a group of suspects so; one DNA sample can lead the investigators to a large network of suspects.

The CCTV (Closed Circuit Television) and ANPR (Automatic Number Plate recognition) .There are huge number of the cameras that cover every street in the city and linked to the central police and the patrol police cars are also supplied with this technology which allow them to recognize the wanted vehicle automatically through its plate number.

Crime costs the British economy about £ 50 billion so; the crime prevention is very important strategy. Prevention comes as first priority to protect innocent people.

Biometric: recognizing people through their eyes (Iris) which is more accurate than the finger print or recognizing their facial features. it depends on the tridimensional measurement of the face. This technique is used in the airports, immigration centre and banks
So they store thousand of images on the database and use this software to identify people but it is difficult to do that in case of crowd and when the cameras are fixed at high position according to the person.
Video surveillance in London underground and how it is useful to identify any suspicious or suicidal behaviors. Identifying unattained packages and prevent any terrorist attack.
Another prevention approach is clothes, animal tagging and destroying stolen CDs by remote device.

Finally they arrested the criminal

Logical end
The End