1. An image coding method for coding a current block, comprising: deriving a first candidate having a first motion vector that has been used to code a first block; determining whether or not a total number of one or more candidates having the first candidate is less than a maximum candidate number; deriving a second candidate having a second motion vector when the total number of the one or more candidates having the first candidate is less than the maximum candidate number, the second candidate being different from the first candidate; and coding an index corresponding to a candidate having a motion vector, wherein the maximum candidate number is used to code the index, wherein the motion vector is used to code the current block, and wherein the candidate is one of a plurality of candidates having the first candidate and the second candidate.