This phrase often implies a level of trust in the person given freedom.

Granting Trust

It doesn't necessarily mean you can do anything; there are still unspoken rules.

Not Literal

With the freedom comes the expectation to respect and care for the place or situation.

It can suggest exclusive access to a place during a particular time.

The freedom is often for a limited duration, not permanent.

This phrase can reflect a special privilege granted by authority figures or institutions.

Being given such access can be seen as a sign of trustworthiness.