Starting in July 2017, the eligibility of several members of the Parliament of Australia was questioned. Referred to by some as a "constitutional crisis", fifteen sitting politicians were ruled ineligible by the High Court of Australia (sitting as the Court of Disputed Returns) or resigned pre-emptively. The situation arose from section 44(i) of the Australian Constitution, which prohibits parliamentarians from having allegiance to a foreign power, especially citizenship. On that basis, the High Court had previously held that dual citizens are ineligible for election unless they have taken "reasonable steps" to renounce the foreign citizenship before nomination.