Sorry, I took that statistic from that fbi.gov violent crime section and left out the part about of those who are "known". Without me accidentally misquoting it, it says:
"In incidents of murder where the relationships of murder victims and offenders were known, 21.6 percent of victims were slain by family members, 23.1 percent were murdered by strangers, and 55.3 percent were killed by someone with whom they were acquainted (neighbor, friend, boyfriend, etc.)."
http://www.fbi.gov/ucr/cius2006/offenses/expanded_information/homicide.html
Doesn't "Expanded Homicide Data Table 9" say at the bottom "1 Relationship is that of victim to offender." So the 1,905 would be 1,905 victims were strangers to the assailant, 6,750 of the victims were unknown as to what their relationship with the assailant was? Like for husband it says 123, while for wife it says 567 (hmmm, that's making me nervous, what if I get married and my wife kills me
j/k). But then the outcome would usually be the same, if the victim was a stranger to the assailant, the assailant was probably a stranger to the victim, and so forth. And stranger murders are probably more difficult to solve and prosecute.
So from how this sounds, maybe this is more reason to take responsibility for your own protection. If it's unknown what many of these victims were to their assailant, then there's probably a huge chunk of murder mysteries that are never solved and they may never solve your murder if you don't take self-defense seriously
Do they have some statistics on that? Out of all reported murders, what percentage of that do they charge someone with murder and take it to trial, and what percentage someone is actually convicted?