A Nigerian man, originally sentenced to death for importing nearly 2kg of methamphetamine, commonly known as Ice, escaped the gallows yesterday after he was cleared on appeal.

In handing down the acquittal, the Court of Appeal said the prosecution had failed to establish that Adili Chibuike Ejike knew that the drug bundles in his suitcase were in his possession.

The three-judge court, led by Chief Justice Sundaresh Menon, disagreed with the prosecution that Adili had been "wilfully blind" to the existence of the drugs.

Even if the Nigerian had taken reasonable steps to check the contents of his suitcase, he would not have discovered the drugs, which were found only when the inner lining was cut open by the authorities, said the court.

"Wilful blindness" is a legal term to describe a person deliberately shutting his eyes to the truth, and entails that had he opened his eyes, he would have seen it.

The court ruled that someone is wilfully blind if it is proved that he had a clear and grounded suspicion, that he had reasonable means of inquiry, and that he deliberately refused to pursue the inquiry.

In November 2011, Adili, who was 28 at the time, arrived at Changi Airport with a small suitcase. After an X-ray scan showed an area of darker density, immigration officers cut the inner lining of the bag, revealing two bundles. These were later found to contain 1.96kg of Ice.

Adili, who was unemployed, said a childhood friend in Nigeria had agreed to give him some financial help if he delivered the suitcase together with some money to an unspecified person in Singapore.

The trial focused on his knowledge about the contents of the suitcase, as both the prosecution and the defence agreed that he was in possession of the drugs.

The defence argued that Adili did not know the bundles of Ice were in the suitcase.

The prosecution's case was that he had failed to rebut the presumption of knowledge under the Misuse of Drugs Act.

The prosecution argued that the circumstances surrounding Adili's task were extremely suspicious and he was wilfully blind by failing to find out what he had been tasked with delivering.

At the end of Adili's trial, a High Court judge had rejected his testimony and found him guilty.

Adili appealed against his conviction and death sentence.

Yesterday, in a written judgment, the apex court said the focus of the case should really be whether Adili was, as a matter of law, in possession of the drugs. This was because "possession" in this context required not just physical custody but also knowledge. The court said a person must know about the existence of a thing before he can be said to "possess" it in a legal sense.

The prosecution's argument that Adili was wilfully blind implies that it accepts that he did not actually know of the existence of the drugs, said the court. Therefore, the prosecution cannot invoke the presumption of possession in this case.

What is left is for prosecutors to prove beyond reasonable doubt that Adili had been wilfully blind to the existence of the hidden drugs, said the court.

"However, it is clear to us that a person opening the case and checking through its contents would not have been able to discover the drug bundles, which were eventually found hidden within its inner lining," said the court.

Hence, the court concluded that Adili was not wilfully blind.