Taiwan in 2004 was already polarized between the Pan-Green coalition, which favored a distinct Taiwanese identity, and the Pan-Blue coalition, which maintained closer ties to mainland Chinese heritage. President Chen's Democratic Progressive Party represented the former; his challenger Lien Chan represented the latter. The shooting, one day before voters went to the polls, immediately became a political Rorschach test. Pan-Blue supporters theorized the incident was staged to win sympathy votes. Pan-Green supporters suggested Beijing's involvement. The Taiwan dollar dipped 0.2 percent and recovered. The real damage was to public trust. When Chen won reelection the next day by the narrowest margin in Taiwan's democratic history, the losing side had already decided the result was illegitimate.

The investigation that followed satisfied almost no one. Forensic scientist Henry Lee, renowned for his work on major American criminal cases, submitted a 130-page report concluding the shooting was not a professional political assassination, because a more powerful weapon than a homemade pistol would have been used. His findings angered conspiracy theorists on both sides. In September 2004, police raided an illegal weapons factory near Tainan and found bullets matching those from the crime scene. The Pan-Blue-controlled legislature established a special truth commission with sweeping powers to investigate, including the authority to override court verdicts and suspend the right to silence. The Pan-Green coalition challenged its constitutionality.

In March 2005, Taiwanese police named two suspects: Chen Yi-hsiung and Huang Hung-Ren. Both were already dead. Chen Yi-hsiung had been found drowned in Anping Harbor on March 28, 2004, nine days after the shooting. He matched a figure caught on security footage near the scene, the so-called "yellow coat bald guy." His family said he had left suicide notes, though they had burned them. Huang had also died by suicide, using a gun made by the same manufacturer as the weapon used in the shooting. The case was officially closed in August 2005 with all evidence pointing to Chen Yi-hsiung as the lone gunman. A China Times poll showed only 19 percent of respondents believed the investigation had been thorough enough.

The March 19 incident remains one of Taiwan's most debated political events. Lien Chan publicly expressed disbelief in the official findings. Vice President Lu herself later called for renewed investigation, pointing toward Beijing. The incident was dramatized in a 2019 film directed by Fu Changfeng. For Tainan, the city where the shooting took place on a crowded campaign street, the event is a reminder that Taiwan's democratic experiment, however vibrant, carries scars. The intersection where the shots were fired looks like any other urban thoroughfare. Nothing marks it. The absence itself is a kind of statement about a wound that neither healed nor was fully examined.