Several theories emerge when analyzing John's disappearance within the context of similar cases:
Mental Health Crisis Theory: Given John's documented depression and failure to take medication, one possibility is that he experienced a mental health crisis that led to impulsive actions. Research shows that individuals with untreated mental illness are at significantly higher risk for both suicide and going missing. The Christmas Eve timing could have intensified feelings of desperation or hopelessness.
Suicide by Drowning Theory: Saint John's location on the Bay of Fundy and Saint John River provides numerous water access points. Studies of missing persons who later died by suicide show they often travel to water sources or remote locations. The winter conditions in December 1998 would have made water temperatures particularly dangerous, with hypothermia occurring rapidly.
Deliberate Disappearance Theory: Some missing persons cases involve individuals who deliberately disappear to start new lives elsewhere. However, this seems less likely given John's mental health struggles and the lack of any subsequent contact with family members over more than two decades.
Foul Play Theory: While there's no specific evidence suggesting foul play, the complete lack of traces or sightings over 26 years raises questions. However, the absence of evidence of criminal activity makes this theory less probable than scenarios involving mental health crisis.