We now know our intelligence services were supporting kill missions in the War on Terror while worrying about the definition of an "acceptable level of collateral damage" when targeting high-value targets.
It came with knowledge that our contribution to that war extended beyond soldiers building schools in Afghanistan and Iraq, or our Special Air Service (NZSAS) carrying out targeted missions in limited deployments.
Importantly, it didn't extend to being complicit in the CIA's 2001-2006 rendition and torture programme.
We benefited from the intelligence gleaned. We even provided questions to be asked of Al Qaeda's propaganda chief Khalid Sheikh Mohammed, who was waterboarded 183 times during interrogations that produced 831 intelligence reports.
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We never asked where the information was coming from, even when information in the public domain raised questions about the methods employed by the CIA.
We didn't do so because we didn't want to upset the United States, which - when rounding up support against Al Qaeda - was finally letting us again be a proper member of the Five Eyes intelligence sharing group.
We know all this because it was in the final report of Inspector General of Intelligence and Security Cheryl Gwyn, who has now left the role to become Justice Cheryl Gwyn of the High Court.
And now the Prime Minister must choose a new Inspector-General of Intelligence and Security.
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The IGIS has oversight of our intelligence agencies, with greater powers and responsibilities than most of her predecessors. The expanded role was Parliament's trade-off for the Kim Dotcom spying debacle and greater powers for the spies, including the legal right to spy on New Zealanders.
Under Gwyn, the office has issued a series of excoriating reports on the NZ Security Intelligence Service (SIS) and the Government Communications Security Bureau (GCSB). It has highlighted legal breaches by the agencies and disagreements over interpretation of the law.
Gwyn has also raised repeated questions over the quality of the information in warrants sought by the NZSIS and GCSB, resulting in some being drafted in a tighter, more constrained fashion.
Those closest to intelligence operations have not always shared Gwyn's enthusiasm for legal exactitude in drawing a line between lawful and not. There has been frustration, some over whether her oversight interferes with the spies' ability to do their job - protecting New Zealand.
In contrast, Gwyn's uncompromising tenure - and legislation she operated under - has given the public more knowledge and greater confidence in the lawful operation of its intelligence agencies.
Will it continue? Where to strike the balance? That's a decision for Jacinda Ardern, who chooses Gwyn's replacement, and Parliament, which approves the choice.