And after a judicial review, the Supreme Court ordered another inquest in 2010 into Private Smith's death.
Her son is one of six British soldiers to have died of heatstroke during the past decade.
The Mo D behaved "as more interested in a PR exercise and covering their backs than being open and honest," she claimed.
"I firmly believe that information was deliberately withheld from not only myself but also the Coroner." Mrs Smith had to fight a legal battle to get a second inquest into her son's death after it emerged that the Ministry of Defence had failed to disclose a Board of Inquiry report during the original inquest.
"Five litres was not an adequate amount of water." The guidelines were "written for Salisbury Plain, not Al Amarah," he said.
The heat was so extreme that soldiers would not wear body armour at times - the risk of succumbing to heatstroke deemed more serious than that of being shot.