Tuen Mun shooting: Drug abuse and mental illness linked to high-risk cases

A 34-year-old Vietnamese man surnamed Bùi, killed by police gunfire in Tuen Mun on January 15 after wielding a knife, had a history of drug abuse and over 10 years of mental illness but recently stopped follow-up treatment.

Psychiatrist Dr. Ting Sik-chuen said drug abuse is a common feature among high-risk psychiatric patients and can trigger or worsen symptoms such as hallucinations, delusions, and mood swings—similar to those in schizophrenia.

While mental illness does not equate to violence, studies show the risk of violence rises significantly during relapse or acute episodes influenced by delusions and hallucinations.

Dr Ting noted most psychiatric treatment in Hong Kong is voluntary. 

For high-risk patients who frequently relapse, abuse drugs, lack insight, and have violent records, he suggested re-examining the feasibility of introducing a Community Treatment Order to ensure regular treatment and monitoring.

He added that the suspect’s refusal of care and prolonged unmedicated state likely raised the relapse risk sharply: about 30 percent of patients relapse about a month after coming off medication, with the probability becoming extremely high after six months.