Thank you for your question. I look forward to working with you to provide you the information you are seeking for educational purposes only.
Even though a person is not hurt and damages only their property, if the police come out and they have reason to suspect DUI they can make an arrest. However, there are numerous fact specific cases on searches pursuant to a DUI search, for example Navarette v. California, 572 U.S. ___ (2014), where the US Supreme court held that if the police have probable cause
for the stop and further have proof of impairment of the driver, a search of the vehicle subsequent to the arrest would be proper and not a violation of the 4th Amendment. However, in Arizona v. Gant, 556 U.S. 332 (2009), the court held that police may search the passenger compartment of a vehicle, incident to a recent occupant's arrest (and therefore without a warrant) only if it is reasonable to believe that the arrestee might access the vehicle at the time of the search, or that the vehicle contains evidence of the offense of arrest.
So as you can see, the very specific facts of each case will determine whether or not the search is valid.
The ruling would apply in American Samoa as the High Court of American Samoa is under the US Supreme Court and any violations of the US Constitution would be heard in the US District Court in Hawaii or US District Court in D.C.