This is fascinating stuff, as much for the blood and gore of Age of Sail naval warfare as for the legal complications associated with impressed Americans in the War of 1812:
At Plymouth we heard some vague rumors of a declaration of war against America. More than this, we could not learn, since the utmost care was taken to prevent our being fully informed. The reason of this secrecy was, probably, because we had several Americans in our crew, most of whom were pressed men, as before stated. These men, had they been certain that war had broken out, would have given themselves up as prisoners of war, and claimed exemption from that unjust service, which compelled them to act with the enemies of their country.
This was a privilege which the magnanimity of our officers ought to have offered them. They had already perpetrated a grievous wrong upon them in impressing them; it was adding cruelty to injustice to compel their service in a war against their own nation. But the difficulty with naval officers is, that they do not treat with a sailor as with a man. They know what is fitting between each other as officers; but they treat their crews on another principle; they are apt to look at them as pieces of living mechanism, born to serve, to obey their orders, and administer to their wishes without complaint. This is alike a bad morality and a bad philosophy.