This may be an 'off-the-wall' thought, but I've wondered about the possibility that Casey's google searches could be for information verification...
--TV programs, such as CSI, Myth Busters, First 48, etc delve into details of death previously unknown to anyone outside the 'real' career field. I've often questioned the wisdom of educating the public by presenting a "How-To" manual for murder, and/or getting away with murder.
--perhaps these google searches were sparked from something she saw on one these types of shows; an effort to verify the possible means of committing a murder, or to garner more information (such as where to hit some one's head via a shovel in order to kill them/cause paralysis/ OR how to break one's neck using said shovel...
Just a thought...:waitasec: