Migration – Refugee status – Section 91R(1)(b) of Migration Act 1958 (Cth) provides persecution must involve "serious harm to the person" – Section 91R(2)(a) lists "threat to the person's life or liberty" as instance of serious harm – Where person faces period or periods of temporary detention – Whether that constitutes "threat to liberty" amounting to serious harm, without qualification as to severity of threat. Migration – Refugee status – Section 91R(1)(a) of Migration Act 1958 (Cth) requires Refugees Convention reason to be "essential and significant reason" for persecution – Where Federal Court held there was failure to accord procedural fairness to claimant – Whether independent merits reviewer failed to draw claimant's attention to relevant issue or information – Whether no fair opportunity to address argument that could materially affect assessment. Words and phrases – "persecution", "serious harm", "threat to life or liberty". Migration Act 1958 (Cth), ss 91R(1)(a), 91R(1)(b), 91R(2)(a). Convention relating to the Status of Refugees (1951) as amended by the Protocol relating to the Status of Refugees (1967), Art 1A(2).