because it's already been identified and proven that IHH organized this nice trip and they are a terrorist group, moreover, this trip was a complete act of provocation with only incitement and martyrdom in mind, not "peace" for gazans. They also were videotaped chanting death to Israel and saying they wanted to die during this journey!!
Shaffir to Herzog: Opposition failed to show leadership in political battles against PM (Haaretz)
from the article: UN rights body names team to probe Gaza flotilla raid