As far as political motives are concerned, nobody in Palestinians top leadership that wanted him death more than Mohammad Dahlan. The whole truth about is going to be revealed sooner rather than later. Dahlan is wrong if he think is going to get away with the crimes. Abbas knew that, Shaul Mofaz knew that, as much as Ariel Sharon knew about this conspirasy to kill ABU AMMAR.
Zionist Union announces support for so-called anti-terrorism bill (Haaretz)
from the article: Arafat aide calls on Chirac to reveal truth about Arafat's death