Where They Read Crime's Clues

Rupert Grint attends the "Harry Potter And The Order Of The Phoenix" UK premiere held at the Odeon Leicester Square on July 3, 2007, in London.
Among the best forensic teams in the world are those in Toronto, Canada – at the Toronto Police Laboratory and at the Center of Forensic Sciences. CBS News Correspondent Randall Pinkston reports.

At the Toronto Police lab, Detective Al Pollard showed the techniques that are used to lift fingerprints.

"Is it possible to wash away blood stains?" asked Pinkston.

"Basically, no," Pollard responded. "We have chemicals that are blood reagents. They react with a trillion parts, very small amount of blood, and we can find the blood."

Ultraviolet light is useful, but even more helpful is laser light.

"Laser light has more energy," explained Pollard.

For now, the laser is used mostly in the laboratory. A portable model is in development, and when it becomes available, it will light the way to even more evidence for crime scene investigators in the field.

The staff at the Center of Forensic Sciences is completely independent of the police. They are the ones who test DNA results, and they have helped solve dozens of U.S. cases.

Pinkston also talked to Joel Mayer, the deputy director of scientific affairs at the Center of Forensic Sciences. Why do agencies sometimes go outside their own countries in search of impartial results in high-profile cases? Interestingly, Mayer says Canadian law enforcement sometimes goes to the United Kingdom for the same reason.

Mayer runs a civilian lab, attached to the Ministry of the Solicitor General. They do work for any party in a criminal case, including the defense.

Mayer says the labs' role is not to convict.

"Our role is to generate scientific findings...and if the answers that come back are not consistent with the theories that investigators develop, I say, 'Well, let's revisit that theory.'"

For more details, visit the Web site for Toronto Police Forensics.

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