No, that's not true. Whites are only responsible for 55% of all American serial killings, even though they represent 70% of the American population.
What the police and media were doing (as did you, as I seem to recall you making bizarre claims that the killer was a young white male American) was policing based upon their own personal racial biases.
They were looking exclusively for an angry white male American, even though angry white male Americans aren't exactly known for writing notes in poor English that say "word is bond".
The snipers were able to pass through ten police checkpoints at ten different shooting locations and have their car tag run each time without triggering the invasive vehicle searches that were going on for all white males driving white vans. This had NOTHING to do with the evidence at hand and EVERYTHING to do with their own personal racial biases.
Moreover, the killers were maintaining strict "one shot, one kill" discipline; hardly a trait associated with their published profile of a Y-Generation 20 year old instant-gratification kid.
In short, the only reason that the killers were caught is because they called the cops so much that they finally slipped and handed the police a clue that amounted to a confession.
But wait, even then the police almost blew it. The cops hung up on the kid 6 times in a row because they were so racially biased that they didn't take a Black Jamaican teenager seriously. The police were listening for an angry white male to call them up, and that never happened.