In the United States, many of our freedoms are covered under documents like the Bill of Rights, but others are considered more of a legal privilege that can be revoked under certain circumstances.
Consider the ability to drive a car. The age at which you can obtain a permit, a restricted license, and a full license varies from state to state. There is nothing in the Bill of Rights that guarantees each American citizen the right to drive a car, so the ability to do so is a legal privilege. As long as drivers follow the established rules, they are free to keep this privilege. However, a driver who accumulates too many speeding tickets, is convicted of a DUI, or uses a vehicle to commit a crime provides evidence that he or she is not trustworthy of maintaining what is needed to be a responsible driver, and that privilege may be suspended.
Another privilege Americans enjoy is the writ of habeas corpus. In this case, a person who feels that he has been wrongfully imprisoned can provide evidence to a judge, who can then review the evidence and potentially release the person from custody. During times of war, presidents sometimes choose to suspend this privilege, taking away the ability of prisoners to protest their imprisonment without the full and expected legal process.