The most active KLA military commanders (Remi, Gashi, Bardhi, et. al.) have been arrested and found guilty by UNMIK/KFOR for murdering Albanians before March 23rd 1999.
2) Detailed examination of the specific body count (there was a tally posted on FR a while back) indicates that KLA/NATO action was responsible for upwards of 80% of non-combatant deaths in Kosovo and Metohija
3) One can also establish the guilt of the KLA and their allies (ie Hoplite) by careful review of the ICTY hearings and cross examination of Prosecution witnesses by President Milosevic. After 2 plus years, the Prosecution witnesses have only served to bloster the defense case.