California Center for Population Research

Over the past decades there has been a growing demand for accurate demographic statistics on same-sex couples, for the purpose of informing such policy debates as marriage equality, domestic partner benefits, and adoption rights for same-sex couples. In response to this demand, statistical agencies such as the United States Census Bureau are making an effort to collect consistent and accurate data on same-sex partners. In this paper we discuss procedures used by the Census Bureau in collecting and reporting data on same-sex unmarried partners in the 2000 Decennial Census, highlighting a serious measurement error problem. Our work serves as a cautionary tale for statistical agencies collecting data on same-sex couples, and as a guide for researchers who use existing data on same-sex couples.