therefore continued, though without, at least on a legal basis the presence of British slavers. However, in 1810, under considerable diplomatic pressure, a convention with Portugal was signed widening the mandate of the Royal Navy. In 1815, Portugal strengthened their anti-slavery legislation by abolishing all trade north of the equator, allowing the Royal Navy a much freer hand. With the conclusion of the Napoleonic Wars, Britain obtained treaties with several other powers including France, which abolished its trade entirely in 1815 (but did not commit to right of search), and Spain, which agreed to cease trade north of the equator in 1818, and south of the equator by 1820. A clause was also inserted into the Congress of Vienna which called for the eventual abolition of the trade by all signatories. In 1826, Brazil signed an agreement similar to that of Portugal, and ceased trade north of the equator. The UK's slave trade suppression efforts attempted to remain within the primitive international laws of the time: slavers had to be tried in courts. British vessels were taken to vice admiralty courts, and those of foreign states which had treaties with the UK were taken to Courts of Mixed Commission. Mixed Commission Courts had representation from both the UK and the other nation in question, to ensure a fair trial. Many were established at key points along the coast of Africa and its islands. However the reluctance of other powers greatly curtailed the ability of the courts to operate; sometimes the foreign representation would never arrive, or arrive exceptionally late. The Brazilian ambassador, in spite of the court opening in 1826, did not arrive until 1828, and he reversed all judgements carried out in his absence upon his arrival. In addition to the issues with Mixed Commission Courts, the Navy's mandate to police the trade was also found to be lacking and built on a series of complicated and often weak diplomatic treaties between other states. The agreements were signed reluctantly and therefore very weak in practice. When policing foreign vessels, there had to be slaves on board at the time of seizure for the accused slaver to be convicted. Unlike in Britain's 1807 act, there was no equipment clause, meaning that slave ships carrying what was obviously equipment for transporting slaves, but without slaves on board at the time of search, could not be seized. This major flaw, which greatly