The ruling makes clear that the state cannot avoid liability for unlawful immigration detention, potentially costing tens of millions in compensation for former detainees, including those once classified as criminals.

Reaction from officials is cautious while legal groups urge prioritizing redress for detention harms and costs.

The government says it is reviewing the judgment and its implications, while opposition figures argue it increases financial liabilities and underscores policy failures at the border.

Legal advocates warn the decision has broad implications for redress for unlawfully detained individuals and could limit the government’s ability to rely on mistaken-law defenses.

The case centers on interpreting unlawful detention within immigration policy and its financial impact on the state.

The ruling holds that granting immunity would invert constitutional principles and wrongly shield Commonwealth officers from unlawful acts.

The decision does not automatically award compensation to all detainees; it removes a key defence and leaves later claims to be determined case by case.

Analysts note the ruling could broaden liabilities for the Commonwealth related to immigration detention practices.

The High Court unanimously ruled that the Commonwealth cannot claim immunity from compensation claims by non-citizens held in immigration detention, potentially exposing the government to multi-million dollar damages.

In Abdel-Hady v Commonwealth, the High Court rejected the government’s immunity defense and opened the door to hundreds of possible compensation claims by unlawfully detained non-citizens.

The ruling opens the possibility for more than 300 individuals from the NZYQ cohort to pursue compensation after their release from indefinite detention.

This follows the November 2023 NZYQ decision, which freed stateless or refugee detainees and sparked a potential wave of claims.