Because they could be used to examine things that human eyes can’t, such as finger prints, blood or DNA. Through the use of forensic science, criminal justice systems are able to tell the time of death of an individual and the weapon being used to kill, which all make solving crimes much easier.
The most challenging part of being a forensic scientist in my opinion is to collect all the evidence because you never know when you are done collecting them. It could keep me up all night just thinking about all the possible evidence there could be and you would have to really pay attention to every little detail to get the most accurate results. Analyzing evidences can also be challenging because you need to make sure you’ve got all the correct test results and data and to not give out false information.