1. This was an appeal against the Appellant’s conviction for making a false declaration to obtain registration for carrying on a vocation, contrary to section 37(a) of the Crimes Ordinance (Cap.200) (“CO”). 2. In October 2013, the Appellant submitted to the Nursing Council an application for enrolment as a nurse and a declaration form in which he declared that he had not been convicted of any offence punishable with imprisonment in Hong Kong (the “Declaration Form”). In fact, the Appellant had been convicted in 2007 of two charges of obtaining property by deception for which he was sentenced to seven weeks’ imprisonment for each charge. 3. The prosecution alleged that the Appellant wilfully made the declaration which he knew to be false or fraudulent to procure himself to be registered as an enrolled nurse. 4. At trial, the Appellant argued that he genuinely believed that he was not required to disclose his previous conviction on the Declaration Form due to the provisions of the Rehabilitation of Offenders Ordinance (Cap. 297) (“ROO”). This belief was confirmed by the legal advice obtained by him from the Free Legal Advice Scheme (“Legal Advice”). As understood by the Appellant, the Legal Advice meant that he would be excused from disclosing his previous convictions unless the application form expressly excluded the ROO. Since the Declaration Form did not contain such an express exclusion, the Appellant claimed that he genuinely believed that he could properly declare that he had no previous conviction. 5. After analysing the content of the Legal Advice, the Deputy Magistrate disbelieved the Appellant’s evidence. This was because he was of the view (which the Appellant challenged in this appeal) that the Legal Advice did not convey what the Appellant said it meant. As the Deputy Magistrate understood it, the Legal Advice directed the Appellant to disclose his previous convictions on the Declaration Form. The Deputy Magistrate therefore concluded that the Appellant wilfully and knowingly made a false declaration, and convicted him. 6. The Appellant appealed to the Court of First Instance without challenging this aspect of the findings by the Deputy Magistrate. While the court upheld the Appellant’s conviction on grounds unrelated to the present appeal, the Deputy Judge remarked that the Deputy Magistrate was right in his understanding of the content of the Legal Advice. 7. The Appellant brought a further appeal to the Court of Final Appeal. 8. The central questions in this appeal turned on the construction of section 37(a) of the CO and the meaning of the Legal Advice. Specifically, (a) as a matter of law, whether the prosecution had to prove that the Appellant appreciated the falsity of the declaration and whether a genuine and mistaken belief that the declaration was not false negated the Appellant’s liability; and (b) whether the declaration made by the Appellant was one which he knew to be false. 9. The Court held that the mental element of the offence under section 37(a) of the CO requires the prosecution to prove that the defendant has an appreciation of the falsity of the declaration he is making. If a defendant honestly and genuinely believes that the declaration is not false, even if it is the result of a mistake of law, he cannot be said to know that it is false. In that event, the mental element of the offence will not be established. 10. In this case, the Appellant’s understanding of the Legal Advice was correct. The Deputy Magistrate and Deputy Judge should not have disbelieved the Appellant’s evidence that he held the honest and genuine belief that the declaration was not false. It followed that the prosecution had not proved beyond reasonable doubt that the Appellant knew that the declaration he made was false. Therefore, the basis of his conviction was flawed. DISPOSITION 11. Accordingly, the appeal was unanimously allowed and the Appellant’s conviction quashed.