In view of the above discussions, we hold the confessions of the accused in the present case to be voluntarily and validly made and under Section 15 of TADA confession of an accused is admissible against co-accused as a substantive evidence. Substantive evidence, however, does not necessarily means substantial evidence. It is the quality of evidence that matters. As to what value is to be attached to a confession will fall within the domain of appreciation of evidence. As a matter of prudence court may look for some corroboration if confession is to be used against a co-accused though that will again be with the sphere of appraisal of evidence.