The democratically elected Knesset exercised it's democratic right to overule an official who forbade the investigation.. Seems reasonable. If, as the sixteen signatories of the open letter claim, they have nothing to hide, then all the fuss can die down, particularly since the media does not seem to be supporting the Knesset on this issue.
U.S. deploys more Patriot missiles in South Korea (AP)
from the article: Knesset votes to probe Israeli groups accused of 'delegitimizing' IDF