After arrival in Jamaica, Gregson filed an insurance claim for loss arguing that the Zong did not have enough water to sustain both crew and the human commodities. The insurance underwriter, Thomas Gilbert, disputed the claim citing that the ship had 420 gallons of water aboard when she was inventoried in Jamaica. Despite this the Jamaican court found for the owners. The insurers appealed the case and in the process provoked a great deal of public interest and the attention of Great Britain’s abolitionists. Granville Sharp, the leading abolitionist of the time, used the deaths of the slaves to increase public awareness about the slave trade and further the anti-slavery cause. A London court found for the insurers and held that the cargo had been poorly managed as the captain should have made a suitable allowance of water for each slave. See the report of the case Gregson v. Gilbert, (1783) 3 Doug 232, 99 E.R. 629 through the BLS Library subscription to Justis, the online library of UK, Irish, EU and international case law and legislation.
Sharp, who first used the word massacre, tried unsuccessfully to have criminal charges brought against the Captain, crew, and the owners. Justice John Lee, Great Britain’s Solicitor General, refused to file criminal charges claiming “What is this claim that human people have been thrown overboard? This is a case of chattels or goods. Blacks are goods and property; it is madness to accuse these well-serving honourable men of murder… The case is the same as if wood had been thrown overboard.” The tragedy of the Zong finally led to the passage 50 years later of the Slavery Abolition Act in 1833.