Added after 4 minutes:
theres two problems with these coverups.
1: people have a right to know the truth.
2: nobody has the right to keep such majorly important things a secret from everyone else.
I have some weird logic
That's when your wrong, if in anyway the truth is what harms the public. The goverment cannot tell that specific peice of information. In many religions they believe earth to be the somewhat, generally the only planet with life (exept christianity). If the goverment were to tell the truth of the information they have. It would cause people to lose their religion, it would lose it's purpose, while some will be modified, most of the other religions would probably die out, leaving people with no faith. When people have no faith, they believe in no purpose for their lives, thus making them to steal and kill, or do whatever they please. For some people, religion is the only thing they have that makes them have the will to live on, if they lose that one thing, it would be choas on a massive scale. That's why the goverment is holding secrets, it's protecting us, it's doing what it is suppost to do.
P.S. There's a secret goverment campaign converting more and more countries to christianity, because they believe that is the only religion uneffected by the secret of alien life.