Congress is opening new hearings today into the abuse of prisoners in Iraq, as retired military officials are calling for an independent investigation of the scandal. Iowa Senator Tom Harkin says the hearings -are- needed as, even months later, all of the facts still aren’t known.Harkin says “We’ve got to get to the bottom of what happened and whether this is the result of just a few individuals who ran amuck or was it because of top-down policies approved at the highest levels of the Department of Defense.” Harkin says the U-S has to “clean up our act.” He says the public may be tired of hearing about the Abu Ghraib prison scandal, but the truth must be known.The retired military officers sent President Bush a letter saying the country -quote- “cannot ignore that there are now dozens of well-documented allegations of torture, abuse and otherwise questionable detention practices” in Iraq. The group claims Pentagon investigations lack the needed power to find out what happened.