Has your son checked into law enforcement? There are plenty of jobs that do not involve getting into the nitty gritty of gruesome scenes, ex.) crime analyst/data analyst, civilian report technician, intelligence analyst, even patrol officers typically will not get too involved with scenes and will instead call in detectives for processing while maintaining a secure perimeter. Granted, this would be more localized to a city but some cities see their fair share of homicides and other crime unfortunately.
He may be interested in national homicide stories because that is what is most available (arguably, most sensationalized). You don't see major burglary or robbery patterns with major headlines and stories, but they can be just as fascinating and typically are less violent. Many law enforcement agencies have explorer programs that allow for students to get hands on experience in the field and would look great as an extracurricular for college applications.