Study shows almost half of all Pentagon contracts since 1998 were awarded without full and open competitions.
DEFENSE - ALL ARTICLES
GAO says services may be using flawed data in attempts to comply with 50-50 law.
Air Force official said e-mail records were not relevant to Senate Armed Services Committee investigation.
Committee focuses all its attention on making its case to become a permanent panel.
More soliders may suffer from post-traumatic stress disorder and amputation, says Principi.