It was a cold winter night but when I walked into the room it started to sway. This was the scene of the crime and I needed help to find out who trashed this classroom.

Joan Cartan-Hansen: if you want to solve the crime why don’t you try – science.

Crime scene investigators use tools and skills known as forensic science to analyze the evidence left behind. It helps them find out what happened and maybe who committed the crime. In earlier times people thought they could decide if someone was guilty just by the way they acted. And then sometimes innocent people were convicted of crimes. There needed to be a way to find reliable evidence to clearly identify who was guilty. That’s how forensic science and crime scene investigation started.

Investigators look at evidence from crime scenes very carefully. You know, evidence could be something like soil or plants, footprints, tire tracks, fibers and bullets. Some evidence like fingerprints can be very useful. Every human being’s fingerprints are unique. If investigators find fingerprints, they can compare them to other fingerprints they’ve already identified and see if there’s a match.

Blood and other body products can also be traced to their source. They contain DNA. DNA is in each cell of our body and it is made up of 4 types of chemicals. Scientists use 4 letters – A, G, C, and T to describe those chemicals. They use complex instruments to take the DNA out of the cells, mark it wish fluorescent color and put it into a computer to be read. When they look at the DNA, scientists see the letters repeating in certain patterns. If the DNA patterns in samples found at the crime scene match the DNA patterns taken from a person, then the scientists can tie that person to the crime scene.

Not all forensic scientists work on human crimes. Some investigators work for the Idaho Department of Fish and Game. They help solve crimes like poaching or help biologists find out exactly what kind of species an animal is.

Other forensic scientists study dinosaur bones to learn how the creatures lived, or study the remains of ancient people to learn more about their culture. These scientists are trying to learn how King Tut, the ancient Egyptian ruler died. You can learn to be a forensic scientist too. These students are taking a forensic science class at the Discovery Center of Idaho.

So we can use forensic science to find out who made this mess?

Joan: possibly, but you know it takes training to learn how to collect evidence and then make sure that it’s not contaminated.

Well, okay, let’s go learn more about this forensic science. Whoever committed this crime must be really smart.

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