This is a highly emotive issue and I appreciate the depth of your concerns for the welfare of our animals and wildlife.
The Hunting Act 2004 makes it an offence to hunt a wild mammal with dogs except where it is carried out in accordance with the exemptions in the Act. Those found guilty under the law are subject to its full force. The investigation and prosecution of all criminal offences, including consideration of whether an actual offence has been committed, is a matter for the police and Crown Prosecution Service, who have comprehensive powers to take action under criminal law. The Government was elected on a manifesto which committed to not amending the Hunting Act.
Since the introduction of the Hunting Act 2004, many hunts have turned to trail hunting as an alternative to live quarry hunting. This involves a pack of hounds following an artificially laid, animal-based scent so does not involve a hunt for a live fox, and therefore is not banned. For an offence to be committed it is necessary to prove that a wild animal is being hunted intentionally. If proven, this can lead to a prosecution and an unlimited fine.
Anyone who believes that an offence has taken place during a hunt, including during a trail hunt, should report the matter to the police.