Yes, these have already been mentioned in this thread. While they do fracture, they do not disintegrate, and they do still leave forensic evidence -- and nothing about the window shatterings has suggested they were used. If they had been used in even one of the window shatterings, LE would be all over it. So, it's a nice theory, but it has nothing to do with the window shatterings.
<BBM for Focus>
Frangibles, absolutely do disintegrate and leave no visible evidence to the unsuspecting LEO's naked eye. Many only leave a powdery substance as residue and could be easily confused with being the result of the normal powdery substance residue left after any accidental window shattering...
Car window shatterings are commonly written off by LE as being the result of road debris for obvious reasons. Many, if not most times, random shootings by snipers would also be considered as isolated incidents of road rage by LE. As in the 2014 KC Sniper; Mohammad Whitacker, trail of terror. The dots were not connected until a pattern of highway and roadway shootings were identified by a police analyst. This is due to jurisdictional linkage blindness/lack of communication between law enforcement agencies. There were four Kansas City cases and three cases from other cities that bore similarities.
There is no logical explanation for CR having three entrance/exit wounds to her neck other than a frangible bullet, imo.
It is very doubtful if task force investigators would release this hold back info to the public, as only the shooter would know whether frangibles were used.. Frangibles which shatters into many small pieces on impact, also cause gun barrel tinning, which prevents positive ballistic identification..
Colorado police check if killing linked to 2 other shootings
http://www.cnn.com/2015/06/04/us/colorado-shootings/
Local APRIL 11, 2014
Police link 12 area roadway shootings
http://www.kansascity.com/news/local/article344861/Police-link-12-area-roadway-shootings.html
Investigators first noticed the pattern of highway and roadway shootings in early April, when a police analyst identified four Kansas City cases and three cases from other cities that bore similarities. Police eventually identified about 20 shooting cases from March and April that could be related.
Other frangible bullets are made from a matrix of powdered copper and nylon. These are injection molded and also completely disintegrate
http://www.shootingillustrated.com/articles/2011/3/25/frangible-ammo/
http://www.ncpa.org/pub/bg160?pg=4
ICC Ammo Frangible Ammunition Booth Ballistics gel testing Shot Show 2014
[video=youtube;9pBrwFld-V4]https://www.youtube.com/watch?v=9pBrwFld-V4[/video]