The effect of a DUI on ones immigration status depends on the various circumstances. If you are an undocumented immigrant, a DUI arrest can lead to immigration proceedings and possibly deportation. If you are in the US legally, a single DUI conviction will not result in deportation.
However, a DUI charge can have adverse immigration consequences. If a DUI is combined with other criminal charges, its charged as a felony, or you have multiple in a certain time frame, a DUI could prevent showing ‘good moral character', potential lead to deportation, or make a non-citizen inadmissible. Also, if the DUI involves illegal drugs, driving on a suspended license, or with a child in the car, the DUI may be viewed as criminal intent and could result in deportation.
Additionally, DUIs do count against you in some immigration applications, such as the naturalization process or DACA. For both of these applications, one must show that they are of ‘good moral character' and a DUI can prevent this.
Getting your DUI expunged or reduced to a lesser charge may help you avoid immigration status issues. Hiring a lawyer who knows California DUI laws inside and out and has experience in negotiating and defending DUI cases may be the best way to protect your future.