If you are arrested in California for driving with a blood alcohol concentration (BAC) of 0.08% with an out-of-state driver's license, your driver's license will not be immediately confiscated.  However, you will be notified that your driving privileges in the state of California will be suspended in thirty (30) days.

Wow, just reading that aloud for the first time probably sounds like you are getting off easy.  Especially if your appearance in California was for a vacation, holiday, or once-in-a-lifetime visit. However, that initial reaction is misguided.  And it is probably because of a misunderstanding of automobile law, the distinction between driving privileges versus a driver's license, and the interconnectivity between the states.  

A drivers license does not convey any special or inherent powers in of itself. Rather, it is merely physical manifestation of possessing a privilege to drive, subject to any conditions set forth thereon. Furthermore, it identifies the issuing state.     

So, the fact that your driving privileges in California might be suspended should be a cause for concern.  That is because suspension here will most likely affect your driver's license in your home state.

All but five states (Georgia, Massachusetts, Michigan, Tennessee, and Wisconsin) belong to the Interstate Drivers License Compact (IDLC).  The IDLC revolves around the concept that every driver in the country has a single drivers license and a single driving record.  States belonging to the IDLC report driving arrests (including DUIs) to each other. As a result, your home state will likely take its own action against your driver's license if you suffer a California DUI arrest.

The type and severity of the action will depend on the state in which you live.  Some states will take action if the California DMV suspends your license, while others only take action if you  suffer a criminal conviction.

So, once the police officer or arresting agency notifies you that your driving privileges will be suspended, they automatically notify the California Department of Motor Vehicles (DMV).  And you have ten (10) days from the date of your arrest to challenge that suspension.  If you do not, then the California DMV will suspend your California driving privileges and contact your home state DMV.

To challenge the suspension, you must request a California DMV hearing. This right is available to you regardless of where you reside.  Once a hearing is requested, the driving-privilege-suspension gets postponed pending the outcome of the hearing. And so does reporting back to your home state.  The hearing is an administrative hearing before the DMV.

Please keep in mind that the above is solely concerning driving privileges. If you are arrested for a DUI in California, you will more than likely be facing criminal charges as well.  And that legal matter will be handled in the appropriate Superior Court of the County in California in which the arrest took place.