You generally don’t drag someone into your country to place them in quarantine. They are being held under guard against their will. The standard term for that is arrest.
Completely agree. It makes zero sense. If this is simply to protect the BVI from COVID-19, they should have been warned and escorted back across the border. No contact and zero risk to anyone.
I'd guess there's more to the story or they got tired of warning people and needed to send a message. The timing seems like the perfect time to send a message as USVI charters will be increasing closer to the holiday season. Immigration officers in most countries have a reputation of being strict and that's for a reason. Just because it's normally a "softer" sea border does not make it OK to assume there will be a warning.
I understand boats need to have space to tack but I'm also pretty sure that boat has a engine and not need to tack thru a narrow channel just because they felt like day sailing.
