Abstract: The subject of this research is the formal logical structure of justification of judicial decisions in the case law. The popular opinion state that the method of such substantiation of is the reasoning by analogy. Ambiguity of such concept compels referring to literature on logics, where analogy as a certain type of reasoning often counterpoises deduction and induction. This creates prerequisites for concluding that justification of court decisions can possess principally non-deductive character. Comprehension of this idea presents great complexity for legal experts. In the course of this research the author comes to the conclusion that analogy cannot be presented as a special form of reasoning that counterpoises deduction and induction. It is demonstrated that such reasoning is an essence syllogism, rationale of which can be the principle of analogy of law or something similar. This allows for new formulation and substantiation of the irregular position, at least for Russian legal theory; analogy cannot be considered the main method, even somewhat characteristic for case law, for justification of court decisions.