Social and political complexities are increasing the challenges faced by criminal investigations, though scientific evidence remains primary, a Chinese American forensic expert said.

Henry C. Lee, an 84-year-old forensic scientist and biochemist, spoke on Sept 13 at the School of Visual Arts Theater at a cultural exchange event attended by more than 500 people.

Lee's career spans nearly six decades, and he has taken part in more than 8,000 investigations. In a US News & World Report list of 25 headlines that shaped history, Lee was credited with direct or indirect involvement in 14 of them, including the O.J. Simpson trial, the Sept 11 terrorist attacks, and investigations related to the assassination of former president John F. Kennedy.

"Let the scientific evidence do the talking," he said. Addressing several recent high-profile cases in the US, Lee told China Daily that public debate and social divisions often overshadow the facts.

"That is unfortunate," he said. "The world has changed so much. Geopolitics, political divisions and racial tensions complicate everything. We must learn to respect one another and live together peacefully, instead of confronting each other with violence."

Lee also warned that social media has created "major problems" for criminal investigations.

"It's become a major, major problem, giving influence against criminal investigations," he said. "In the early days, reporters reported facts," he said, adding that now social media sometimes twists facts and writes a story.

Use of AI

Considering the use of artificial intelligence today, he added that although it can be used to fabricate facts and create distracting falsehoods with realistic images and videos that make it harder for readers to tell what is real, Lee acknowledged that AI and other digital tools are playing an increasingly important role in investigative work.

"AI has really taken over many investigative tasks," he said. "More than 20 years ago, we began using tools that weren't called 'AI' — that we called profiling, geographic analysis, big-data methods and logical intelligence — to solve cases."

"Today, CCTV footage alone can solve many crimes: facial recognition, voice analysis, vehicle shape and pattern matching, model and year identification, and automated license-plate reading. GPS and cellphone data let investigators pinpoint locations and communications. Where investigators once labored over paint chips and trace evidence, AI and data analytics now handle much of that work," he added. But Lee was emphatic that technology cannot replace physical evidence.

Lee was appointed Connecticut state police commissioner in 1998, becoming the first Chinese American to hold such a high-ranking post in US law enforcement. He was inducted into Connecticut's Immigrant Heritage Hall of Fame in 2019.

Minlu Zhang in New York contributed to this story.