In the legal sense, the Queen, as the reigning monarch, is generally immune from arrest or prosecution. This principle is known as "sovereign immunity" or "royal prerogative." It is based on the idea that the Queen is the embodiment of the state and cannot be subjected to legal proceedings.
However, it's important to note that sovereign immunity does not mean that the Queen is above the law. In practice, the principle of sovereign immunity ensures that criminal and civil legal proceedings are not initiated against the monarch. Instead, the law applies to individuals who act on behalf of the Queen or hold positions of authority.
While the Queen herself is immune from arrest, it is possible for actions taken by members of the royal family or those acting in their capacity to be subject to legal consequences. The legal framework in this regard can be complex and varies depending on the specific circumstances, jurisdiction, and applicable laws.
It's also worth mentioning that the concept of sovereign immunity may have exceptions in certain situations, such as matters of national security or extraordinary circumstances. Nonetheless, it is highly unlikely that the Queen would face arrest or legal proceedings during her reign due to the application of sovereign immunity.