Bruce Spencer Weir (born 31 December 1943) is a New Zealand biostatistician and statistical geneticist. He is Professor of Biostatistics and Professor of Genome Sciences at the University of Washington. He was previously the William Neal Reynolds Professor of statistics and genetics and director of the Bioinformatics Research Center at North Carolina State University. He is known within academia for his research in statistical and forensic genetics, and outside academia for testifying in the O.J. Simpson murder trial in 1995.