What does Implied Consent mean?
States have implemented implied consent laws which state that drivers have given their "implied consent" to submit to a chemical test of their blood, urine, or breath if they are lawfully arrested for drunk driving. State laws vary, but in many states the police officer will choose which test the driver must take, and if the driver refuses, they will have their license automatically suspended. The license suspension is an administrative penalty and will result in a license suspension, regardless of whether the driver is eventually convicted of drunk driving in a criminal court. In some states the police may have the right to force a driver to take a test, however, given recent Supreme Court rulings they may need a search warrant.
Drivers who have their license suspended under their state's implied consent laws have the right to request an administrative hearing and challenge the suspension. If the court finds in the driver's favor their license is automatically reinstated, although it could be suspended later if they are convicted of DUI.
Generally, it is not a good idea to refuse a chemical test after a DUI arrest. Refusal is no guarantee that you will not be charged and convicted of DUI and in some states the prosecution can use your refusal against you by arguing that you refused the test because you knew that you were intoxicated.