An upper-division forensic chemistry experiment is described. It involves using glycolic acid and sodium glycolate as analogs of [gamma]-hydroxybutyric acid and its sodium salt. The experiment shows the use of silylation in GC-MS analysis and gives students the opportunity to work with a commonly used silylating reagent, N,O-bis[trimethylsilyl]trifluoroacetamide (BSTFA). GC-MS is used to show the problem with analyzing an organic acid without derivatization and to analyze the products of silylation. (Contains 4 figures.)