Because the estoppel doctrine applies in the criminal context to prevent a defendant from profiting from his wrongdoing, a defendant who provides a false identity to avoid a probation search is estopped from then challenging the search as being an invalid probation search. At a 1538.5 hearing, the officer testified that he stopped appellant’s car after noticing that the driver’s side brake light was not operating. Following the stop, appellant identified himself as his brother and said he was on probation but did not indicate if it was searchable probation. He did not have a driver’s license and the record check under the brother’s name revealed that the brother’s license was suspended or revoked. At that point, the officer detained appellant and put him in the back seat of the patrol car. Relying on appellant’s statement that he was on probation, the officer searched appellant’s vehicle and found cocaine base. The appellate court declined to consider appellant’s claim that the search was invalid because the officer did not know he was on searchable probation (People v. Sanders (2003) 31 Cal.4th 1180). Appellant concealed his identity from the officer, which otherwise would have provided the officer with a valid basis for the search. Therefore, he is estopped from challenging the validity of the search.