Human Rights Watch says Israel has not shown it will conduct objective probe . Group also faults its reporting on Gaza conflict , which it is still reviewing . Both sides are reporting on alleged war crimes during Gaza war a year ago . About 40 Palestinians and 13 soldiers were killed during the Israeli incursion .
Human Rights Watch says Israel has not shown it will conduct objective probe . Group also faults Hamas report on Gaza conflict , which it is still reviewing . Both sides are reporting on alleged war crimes during Gaza conflict a year ago . About 1,400 Palestinians and 13 Israelis were killed during the Israeli incursion .