As per case facts, five persons, including the three appellants, were charged under Section 15 of the NDPS Act for conscious possession of 640 Kgs of poppy husk found in ... a truck. The vehicle was stopped, and while two occupants fled, the driver (Appellant No.3) and two others (Appellants 1 and 2) were apprehended. 16 bags of poppy husk were recovered, samples taken, and contents confirmed as poppy head. The trial court convicted the appellants, which the High Court upheld, rejecting arguments regarding Section 50 compliance and absence of independent witnesses. The appeal challenged the artificiality of the prosecution case, discrepancies, and crucially, the lack of established conscious possession. The question arose whether mere presence in a vehicle containing contraband, without further evidence of control or custody, sufficiently establishes conscious possession under the NDPS Act, especially when the accused were not explicitly questioned about possession during examination. Finally, the Supreme Court ruled that merely being present in the vehicle or sitting on the bags of contraband, without additional proof of custody or control, does not establish possession beyond reasonable doubt. The Court emphasized that the trial and High Courts erroneously relied on the appellants' failure to explain their presence at an odd hour, without adequately addressing the fundamental issue of possession or ensuring that the accused were questioned on this crucial aspect. The non-application of mind to material factors and the incorrect invocation of presumptions under Section 35 and Section 54, which relate to culpable state of mind and burden of proof after possession is established, led to a vitiated judgment. The Court also noted the infirmity in the case against the driver due to the absence of a charge for transporting goods without a permit. Consequently, the conviction and sentence were set aside, and the appeal was allowed.