Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The most common decision criteria for decoding are maximum likelihood decoding and nearest neighbor decoding. It is well known that maximum likelihood decoding coincides with nearest neighbor decoding with respect to the Hamming metric on the binary symmetric channel. In this paper, we study channels and metrics for which those two criteria do and do not coincide for general codes.62311501156Sao Paulo Research Foundation [2013/25977-7]National Science Foundation [DMS-0903517]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)