And if the ship has the misfortune to meet with enemies or pirates, the master must perform the part of a valiant man, and make the best resistance which the comparative strength of his ship and crew will allow.
Per Lord Abinger C. B. in Regina v M'Gregor and Lambert  1 Car & K 428, at p.431-432:
The stat., which is the 11 & 12 Will. III с 7, s. 9, enacts, that, if any person shall lay violent hands on his commander, &c., or make or endeavour to make a revolt in the ship, he shall be deemed a pirate and a robber. This particular offence was not piracy at common law. Piracy at common law involved a charge of robbery; but this Act of Parliament, perhaps the better to preserve order and discipline on board a ship, makes it piracy to create a revolt, or to endeavour to excite a revolt. By revolt I understand something like rebellion or resistance to lawful authority. Persons who rebel against and resist the constituted authorities, if they are subjects, are said to be in a state of revolt, and if the crew of a ship combine together to resist the captain, especially if the object be to deprive him of his authority altogether, it will, the resistance of one person to the authority of the captain would not be a revolt. Revolt means something more than the disobedience of one man.in my opinion, amount to making a revolt. I think, upon the construction of this Act of Parliament, that
The Magellan Pirates  1 Sp Ecc & Ad 81 July 26 1853, per Dr. Lushington at p. 83:
Now, how am I to determine who are pirates, except by the acts that they have committed. I apprehend that, in the administration of our criminal law, generally speaking, all persons are held to he pirates who are found guilty of piratical acts; and piratical acts are robbery and murder upon the high sea. I do not believe that, even where human life was at stake, our Courts of Common Law ever thought it necessary to extend their inquiries further, if it was clearly proved against the accused that they had committed robbery and murder upon the high seas. In that case they were adjudged to be pirates, and suffered accordingly. Whatever may have been the definition in some of the books, and I have been referred by Her Majesty’s advocate to an American case (The United States v Smith, 5 Wheaton 153), where, I believe, all the authorities bearing on this subject are collected, it was never, so far as I am able to find, deemed necessary to inquire whether parties so convicted of these crimes had intended to rob on the high seas, or to murder on the high seas indiscriminately.
The Telegrafo (1871) 8 Moo PC NS 43, per Sir Robert Phillimore at pp.60-61:
That goods piratically taken cannot be transferred to a third party as against their legitimate Owner is an undoubted proposition of public and of international law, but the further and different proposition, that the Ship of the Pirate which has not been taken from another person cannot be transferred to an innocent Purchaser for value, is not supported by any of the authorities cited. The goods of Pirates are forfeited to the Crown in its Office of Admiralty, but not until after conviction, and the Ship of the Pirate, but not until after condemnation; or, as it is correctly stated in Bacon’s Abr., tit. "Piracy,": " the goods of Pirates not taken from others, belong, after attainder, to the Crown or its Grantee: and those of which other been despoiled will be forfeited in the same manner if the Owners come not within a reasonable time to vindicate their property”.
Per Stephen Hofmeyr QC (sitting as a Deputy Judge of the High Court) in The Longchamp  EWHC 3445 (Comm) at para 99:
Pirates are not reasonable people. In the minds of most right-thinking people their behaviour is seldom rational.