Throughout his account of the Dido's campaign against piracy off the coast of Borneo, Henry Keppel reiterated his commitment to both the anti-piracy campaign and James Brooke whom he obviously admired.10 But it has to be noted that at no point in his narrative – in either of the two volumes of his work – did Keppel offer a definition of what piracy was, or what kind of activity would be construed as piratical. At times the haziness of the concept accounted for the mishaps and misunderstandings that occurred during the Dido's stint in Bornean waters, and one of these instances involved the fateful encounter between the armed boats of the Dido and the ships of the Rajah of Riao.

In their zeal to render service to Brooke, the crew of the Dido and the small company of boats made up of the longboat, dingy and pinnace did occasionally step beyond the bounds of propriety and decorum. Keppel recorded one such incident in volume 2 of his work. It involved the longboat and pinnace of the Dido encountering a number of native boats along the Natunas coast. They sped off when they were spotted.

The Dido's boats chased after the vessels, and as soon as they came into range opened fire on the assumption that they were pirates on the run. Amazingly, and for reasons that remain unclear, midway through the fighting the crews of both ships hailed each other to identify themselves. The crew of the native boats proclaimed that they were men of Riao, sent by their rajah to collect tribute from villages that had sworn allegiance to him. The shooting ceased immediately, for the Rajah of Riao was then an ally of the British and by default any actions conducted by men under his command could not be deemed piratical.

The ill-fated encounter with the rajah's fleet – though it ended up with both sides admitting that they were mistaken – is instructive in the sense that it sheds some light on the murkiness of relations between the British (and other Europeans) the native rulers who were recognised as sovereigns (such as the Rajah of Riao and Rajah Muda Hassim of Sarawak) and other native malcontents and undecidables who were summarily lumped together under the generic label of ‘pirate’.