Joji Obara
Joji Obara is a Japanese serial offender responsible for numerous sexual assaults and murders, including the high-profile deaths of Lucie Blackman and Carita Ridgway in the early 2000s. His crimes shocked Japan and the international community due to their scale and brutality. Obara targeted women, often drugging them before carrying out prolonged assaults. His eventual arrest led to a lengthy trial, resulting in a life sentence. The case exposed gaps in law enforcement responses and highlighted the dangers faced by women working in nightlife industries.

Jonathan Valencia
Henry Jonathan Valencia, often referred to as Jonathan Valencia, became known in true crime coverage after the murder of teenager Nosiah Santos during a public confrontation that prosecutors described as emotionally charged and deeply personal. Investigators alleged the killing stemmed from a secret relationship, escalating jealousy, and mounting tension between the two young men before the fatal shooting occurred. The case generated major online attention because portions of the confrontation and aftermath were captured on surveillance footage and witness recordings. Prosecutors argued Valencia intentionally targeted Nosiah Santos during the encounter before opening fire in front of witnesses. The combination of hidden relationship allegations, emotional conflict, and public violence turned the case into a heavily discussed modern youth homicide prosecution.
Jonty Bravery
Jonty Bravery is known for throwing a child off a building, as depicted in the documentary

Joran van der Sloot
Joran van der Sloot became internationally infamous after years of deception, manipulation and violent criminal behavior connected to multiple international investigations. Long before receiving a murder conviction in Peru, van der Sloot had already become one of the most recognizable criminal suspects in the world due to his constant media appearances, contradictory statements and apparent obsession with controlling public narratives surrounding himself. Van der Sloot developed a reputation as a pathological liar who repeatedly exploited media attention, manipulated investigators and inserted himself into global headlines for nearly two decades. His later murder conviction and extortion schemes cemented his image as a narcissistic and dangerous offender whose crimes extended far beyond a single homicide investigation.
Jordan Monaghan
Jordan Monaghan is a known killer, featured in multiple true crime documentaries.
Jorge Lachazo
Jorge Lachazo is identified as a 'crazy killer' in the title, implying he has committed a crime.
Joseph Corcoran
Joseph Corcoran is the individual convicted of killing his family, leading to his execution in Indiana
Joseph Edward Duncan
Joseph Edward Duncan, known as 'The Boogeyman', is a serial killer responsible for the murder of a family in Idaho in 2005.