Do you think the government has ever played a role in covering up something?
Watergate comes to mind.
Could you imagine how corrupt the government would seem if we knew about every little thing the government did?
Mostly, they cover things up so as not to worry the people. I'd give an example, but everything the government is *probably* covering up right now is being, well, covered up.
They kept NASA hushed 2 years ago when a large meteor passed by the Earth by a few million miles (almost nothing in astronomical terms). They didn't want panic so they kept it secret until a few weeks ago. When something like that does happen, like it's about to hit us, they'll do the same thing just to avoid a panic.
They cover up a lot of stuff in wars. Look at what Wikileaks is putting out. There's a lot of stuff they don't want released.
The only time a cover up goes to hell is when it goes to the top like Watergate. That was a foolish event.
For those of you who know nothing about Watergate: Nixon was worried that he would lose the next election (even though he had very high approval ratings and won by a lot). The original news story was almost thrown out until it was realized that federal agents were tasked with the raid/wiretaps. (They actually got away with it the first time, but one of the taps failed due to the technology of the time. They went back to fix it, but a rent-a-cop found some tape over a lock on a back door and called the police.) Then as the investigation went deeper, Nixon fired most of his staff, which got people to ask more questions. Eventually, allegations of conspiracy and other things were about to be brought against him and he resigned. He was presidentially pardoned by Ford.
Great commercial idea: Could switching to Geico really save you 15% or more on car insurance? Does the government do cover-ups? Then show the watergate clip from Gump.