The trial was punctuated by legal challenges from island residents, who denied the island's colonial status, and with it the United Kingdom's judicial authority. Defence lawyers for the seven accused men claimed that British sovereignty over the islands was unconstitutional: HMS Bounty mutineers, from whom almost all of the current island population is descended (together with Polynesians), had effectively renounced their British citizenship by committing a capital offence in the burning of the Bounty in 1790, they said. In a symbolic rejection of British rule, islanders still celebrated this act annually by burning an effigy of the Bounty, according to Paul Dacre, the Pitcairn public defender. The defence maintained that the UK never made a formal claim to Pitcairn, and never officially informed the islanders that British legislation, such as the Sexual Offences Act 1956, was applicable to them.
In a judgment delivered on 18 April 2004, the Pitcairn Supreme Court (specially established for the purpose of the trial, consisting of New Zealand judges authorised by the British government) rejected the claim that Pitcairn was not British territory. This decision was upheld in August 2004 by the Pitcairn Court of Appeal, endorsing the claim of Deputy Governor Matthew Forbes that Pitcairn was British territory. A delay of the trial until the United Kingdom's Judicial Committee of the Privy Council (JCPC) decided on an additional appeal was rejected. The trial started on 30 September 2004.
On 12 October 2004, the Privy Council agreed to hear the case against British sovereignty on Pitcairn, but refused to suspend the trials pending the outcome of the hearing. It was announced on 18 October that upon being sentenced, the defendants would be freed on bail until the Privy Council ruled on the constitutionality of the trial. If the Privy Council had ruled in favour of the islanders (which constitutional experts considered unlikely), the trial and its conclusions would have been deemed null and void. The hearings before the Privy Council were expected to last two weeks and to be the longest in more than 100 years.
Verdicts were delivered on 24 October 2004, with all but one of the defendants convicted on at least some of the charges they were facing. Those found guilty were sentenced on 29 October 2004.
The remoteness of Pitcairn (which lies about halfway between New Zealand and Peru) had shielded the tiny population (47 in 2004) from outside scrutiny. The islanders had for many decades tolerated what others classify as sexual promiscuity, even among the very young, claimed to be in line with traditional values of their Polynesian ancestors. This included a corresponding tacit acceptance of behaviour which in the UK would be considered child sexual abuse. Three cases of imprisonment for sex with underage girls were reported in the 1950s.