Following Theresa Duncan's death, various conspiracy theories emerged online, fueled by speculation and rumors about her life, work, and the circumstances surrounding her passing. Some theories suggested that she was involved in secret government programs or that her death was not a suicide.

These conspiracy theories gained traction online, spreading misinformation and fueling further speculation. They were often based on unsubstantiated claims and lacked credible evidence. The spread of these theories contributed to a climate of suspicion and mistrust.

Many researchers, journalists, and commentators have debunked these conspiracy theories, providing evidence-based explanations for Duncan's death and countering the spread of misinformation. Critical analyses of these theories have highlighted their flaws and lack of credibility. However, some of these theories continue to persist online.