Points to be made:

1. NASA is not a monolithic organization. It has groups, individuals and divisions constantly competing for ever-dwindling resources (money).

2. If someone in NASA were to discover evidence of ET intelligence, their section would be awash in cash for decades.

3. That someone would be famous overnight.

4. Keeping someone quiet in NASA is impossible. As evidence, see the recent global warming dustup between Hansen and the Bush Administration. They tried to shut him up, but it didn't work.

5. SETI is a privately funded endeavor.

6. If they were to discover alien signals thier funding problems would be over.

7. Given the stature of SETI in the astronomical field, they would jump at the chance to prove others wrong.

8. I don't have the protocols in front of me, but confirming an alien signal doesn't just involve pointing one receiver at the area and making a recording. It needs to be confirmed by receivers all over the world, with the data then reviewed by many astronmers.

9. Given the earth-shattering news this would generate, there is no way this news could ever, in a million years, be suppressd.