Blood fingerprints are almost the favorite type of fingerprint for forensic scientists.
Compared to ordinary latent fingerprints, blood fingerprints are like the suspect actively applied clay, almost displaying the finest lines of the fingerprint, even more beautifully than clay.
But after wiping, it's a different story.
If fingerprints are wiped while the fresh blood has not dried, the lines are soaked with blood, eliminating the basis for fingerprint comparison.
However, after carefully checking the photos from the "Cuiling 211" crime scene, Jiang Yuan was sure that after wiping their hands on the curtain and towel, the murderer left some fingerprint fragments on the edges.
That is, when the fingers were almost dry but not quite completely wiped, some residual fingerprints were left behind.
Through a simple crime scene reconstruction, it is evident that the murderer wiped their hands with the curtain after killing two people and preparing to go upstairs.
