Later on, however, forensic science began to assume a greater role in criminal investigations, and it often gave rise to conflict between opposing viewpoints. Weng had just graduated from the Central Police College in 1975 and gone to work in the forensics section when he was called upon to review the evidence from a shooting.
當這門新興學科開始挑戰傳統辦案方式時，還引起不少觀念上的衝擊。民國六十四年翁景惠剛從警官學校畢業進刑事局工作，當時有件槍擊案發生，一位外勤偵查員送了槍枝及彈頭前來比對，並指出已經有兇嫌主動投案，承認槍擊案為他所為，請鑑識科鑑識後予以結案。