Which of Grissom's forensic techniques in CSI: Crime Scene Investigation was the most innovative?

Grissom's Forensic Techniques
CSI: Crime Scene Investigation
CSI
TV
Grissom's Forensic Techniques poll options
Grissom's Forensic Techniques
CSI: Crime Scene Investigation
CSI
- Using bugs to determine time of death
- Using luminol to detect blood
- Reconstructing faces from skulls
- Analyzing gunshot residue.