FACTS 1. This appeal concerns the requirement under the common law offence of attempting to pervert the course of justice that the accused’s act has to have a tendency to pervert the course of justice, in the context of an investigation by the Independent Commission Against Corruption(the“ICAC”) against the Appellant. 2. The Appellant used to be a staunch supporter of Mr C Y Leung in his successful bid to become the Chief Executive of the Hong Kong Special Administrative Region (the “CE”). Their relationship turned sour after Mr Leung assumed office. 3. On 8 January 2013, the Appellant was arrested and interviewed by the ICAC on suspicion for having conspired with others to commit an offence contrary to the Prevention of Bribery Ordinance (Cap 201) (the “Investigation”). He was released on bail after the arrest and interview. 4. On 9 January 2013, on the Appellant’s instruction, his personal secretary prepared and sent emails addressed to the CE and the Commissioner of the ICAC (the “Commissioner”). The Appellant protested his innocence in the email and requested the CE and the Commissioner to stop the Investigation, describing it as “groundless” and “political persecution”. The Appellant claimed that if the Investigation was not terminated, “a political bomb would be detonated”. 5. On 10 January 2013, again on the Appellant’s instruction, his personal secretary prepared and delivered a letter addressed to the CE and copied it to the Commissioner. It directly accused the CE of instigating the Investigation and claimed that, if it was not stopped immediately, the Appellant would announce the call for the CE’s resignation to the media and the Central People’s Government using “shocking insider information”. The letter requested the CE to instruct the ICAC to stop the Investigation. 6. In 2015, the Appellant was tried and acquitted on conspiracy charges arising from the Investigation. He was subsequently tried on January 2016 in the District Court on the present charge of doing acts tending and intended to pervert the course of public justice, contrary to common law. The Appellant was accused of seeking to rely on his past dealings and association with the CE, by threat or by intimidation, to influence the CE and/or the Commissioner to terminate the Investigation. 7. On February 2016, the Appellant was convicted in the District Court and sentenced to 18 months’ imprisonment. His conviction was confirmed by the Court of Appeal (“the CA”) in March 2018. 8. In May 2018, the CA certified three points of law of great and general importance for consideration before this Court. The questions were concerned with the nature and details of the CE and Commissioner’s legal powers. They arose from lower courts’ proceedings where the Appellant argued that what he had done had no tendency to pervert the course of justice as neither the CE or the Commissioner had legal power to do what the appellant wanted them to do. The Appeal Committee of this Court added an additional question as a prior question to those identified by the CA, such that the CA’s questions would not arise should the answer to the Appeal Committee’s question be “no”. ISSUES 9. The prior and key question of this appeal was whether, in order to prove that the Appellant’s acts had a tendency to pervert the course of justice, it was necessary for the prosecution to establish that the CE or the Commissioner could, by the lawful exercise of a legal power that he possesses, stop or interfere with the criminal investigation. 10. Setting out the general principles, the Court held that for an act to have a tendency to pervert the course of justice, it must have a tendency to bring about a miscarriage of justice in curial proceedings. This includes acts that have a tendency and are intended to frustrate or deflect the course of imminent, probable or possible curial or tribunal proceedings. The offence may be found on acts of interference in relation to curial proceedings which may result from an investigation. The Court further observed that whether a defendant’s act had the tendency to pervert the course of justice is a question of fact in each case. 11. The CE and the Commissioner are respectively, the head of the HKSAR and of the ICAC. The CE is the person to whom the Commissioner is accountable in respect of his work. The emails and letter were written while the Investigation was ongoing. Both the CE and the Commissioner were relevantly connected with the Investigation. It is plain that writing to them asking them to stop an ongoing ICAC investigation, with the threat that otherwise a huge political bomb would be detonated, involves a tendency to pervert the course of justice. 12. The Appellant’s suggestion that in order for the approaches to them to have a tendency to pervert the course of justice, the CE and the Commissioner must have the legal power to stop the investigation, is unrealistic on the facts of this case. 13. The CE is in a unique constitutional and legal position. He is undoubtedly in a position to influence or otherwise affect the Commissioner’s and, through the Commissioner, his officers’ handling of the investigation, if not to stop it altogether. Whether the CE may or may not be successful is not to the point. 14. Similarly, the Commissioner holds the position as head of the ICAC. There would be many things that he could do, or attempt to do, directly or indirectly, administratively or otherwise, which frustrates, delays or otherwise interferes with the investigation or affects its outcome, even bringing about its termination altogether. 15. The key question above must therefore be answered with a “no”. As such, it is unnecessary to deal with the questions certified by the CA. However, the Court should not be taken as agreeing with the analysis of the lower courts on them. DISPOSITION 16. The appeal was unanimously dismissed.