Abstract
The present study investigates language choice in two bilingual speech communities in the United States: Nogales, AZ and San Ysidro, CA. Ethnically distinct fieldworkers approached members of these two communities under the guise of being lost tourists in order to engage in casual speech encounters. It was found that language choice varied between the two communities, with participants of the San Ysidro community more likely to engage in codeswitching. Ethnicity was also found to be a significant predictor of language choice, with more codeswitching taking place with the fieldworker of a Hispanic phenotype. Potential explanations and factors for future research are discussed.