V. The right to challenge the legality of detention 28. The Basic Principles and Guidelines on Remedies and Procedures on the Right of Anyone Deprived of Their Liberty to Bring Proceedings Before a Court33 applies to all nonnationals, including immigrants regardless of their status, asylum seekers, refugees and stateless persons, in any situation of deprivation of liberty.34 29. The right of anyone deprived of his or her liberty to bring proceedings before a court in order that it may decide without delay on the lawfulness of his or her detention and obtain appropriate remedies upon a successful challenge, is a self-standing human right, the absence of which constitutes a human rights violation.35 This right applies to everyone, including immigrants regardless of their migration status, refugees and asylum seekers and stateless persons.36 30. Any detention in the course of migration proceedings that makes it impossible to mount an effective challenge to the continued detention is arbitrary.37 VI. Respect for rights during detention in the course of migration proceedings 31. Those detained in the course of migration proceedings enjoy the same rights as those detained in the criminal justice or other administrative context, including the rights enshrined in the Body of Principles for the Protection of All Persons under Any Form of Detention or Imprisonment. 32. Those detained in the course of migration proceedings must be treated without discrimination based on race, colour, sex, property, birth, age, national, ethnic or social origin, language, religion, economic condition, political or other opinion, sexual orientation or gender identity, disability, nationality or any other status, or on any ground that aims at or may result in undermining the enjoyment of human rights on the basis of equality. 33. Those detained in the course of migration proceedings have the right to be informed, in writing and in a language which they understand, of the nature of and grounds for the decision to detain, the duration of detention, as well as of the possibility to challenge the legality and arbitrariness of such decision.38 34. All those detained in the course of migration proceedings must be properly informed of their right to seek asylum and be able to file an asylum application.39 35. All detained migrants must have access to legal representation and advice and interpreters, including with the view to challenging the detention order, appealing deportation decisions or preventing cases of refoulement. If necessary, access to free and effective legal aid should be ensured.40 33 A/HRC/30/37. Ibid., para. 8. 35 Ibid., para. 2. 36 Ibid., para. 8. 37 See, for example, opinions No. 42/2017 and No. 28/2017. See also C. v. Australia (CCPR/C/76/D/900/1999); Baban et al. v. Australia (CCPR/C/78/D/1014/2001); Shafiq v. Australia (CCPR/C/88/D/1324/2004); Shams et al. v. Australia (CCPR/C/90/D/1255, 1256, 1259, 1260, 1266, 1268, 1270 & 1288/2004); Bakhtiyari v. Australia (CCPR/C/79/D/1069/2002); D. and E. and their two children v. Australia (CCPR/C/87/D/1050/2002); Nasir v. Australia (CCPR/C/116/D/2229/2012); and F.J. et al. v. Australia (CCPR/C/116/D/2233/2013). 38 See A/HRC/30/37, para. 42. See also E/CN.4/1999/63/Add.3, paras. 27-28; E/CN.4/1999/63/Add.4, paras. 49-50; A/HRC/27/48/Add.2, para. 118 (d) (i) and 119 (b); and A/HRC/10/21/Add.5, para. 76. 39 See, for example, A/HRC/27/48/Add.2, para. 133; A/HRC/30/36/Add.3, para. 80; and A/HRC/10/21/Add.5, para. 76. 40 See, for example, A/HRC/27/48/Add.2, para. 129; A/HRC/30/36/Add.1, para. 90; and A/HRC/33/50/Add.1, paras. 51-54. 34 5