Anyone with an interest in laser and other directed energy weapons should read "Beam Weapons" by Jeff Hecht. It's an older book, but a lot of the info is still relevant. It tells everything you'd want to know about lasers being used as weapons, including what they can and cannot do. It also theorizes the exact amount of laser energy needed to kill a person!
The Doug Beason book is a good read but it focuses mainly on non-lethal stuff and doesn't tackle the issue of causing human death or casualty (deliberately or otherwise) with directed energy weapons.
Here's another "must read" (note - this is PDF file):
Operational implications of laser weapons This one, published by defense contractor Northrup Grumman, does go into detail about what other things laser weapons (not the ABL but smaller tactical lasers) might be used for, including "taking out' individual terrorists and insurgents.
As far as killing personnel, there is really no prohibition on using lasers or other DEWs for that purpose, the only thing that is specifically banned by the Geneva Convention is the purposeful blinding of enemy soldiers by lasers designed solely for that purpose. The UN might cry foul, but what difference would it make if an enemy was shot dead by a gun firing conventional kinetic munitions - or a laser gun firing photons? The only prohibitions (or objections) would arise if a weapon was found to inflict unnecessary suffering, like land mines.
Now as far as the government is officially concerned, the only DEWs being specifically developed as anti-personnel weapons are the non-lethals, like the Active Denial System. But you can bet for sure that there are plenty of "black" laser and DEW programs that are focusing (pardon the pun) on ways to kill enemy personnel!
