Before you can be pulled over for suspicion of driving under the influence in Los Angeles, or before you can be questioned about whether you are intoxicated, the officer must have reasonable cause to do so.
There are certain procedures and steps an officer must follow before they can arrest someone for a Los Angeles DUI. These procedures and rules are put in place to ensure that the driver’s 4th Amendment rights are protected. Your 4th Amendment rights are the rights against unlawful search and seizure granted to you by the United States Constitution. This means that authorities are not able to search your private or personal space without reason to do so. There has to be a reason that would justify violating your privacy in such a manner.
Generally, the first obstacle of reasonable cause is a reason to ask that you pull over. An officer has to have a valid, and legal reason to ask that you pull over. This is generally in the form of a traffic violation. It could be running a red light, running a stop sign, weaving, speeding, etc. An officer cannot arbitrarily stop a person.