Parliament's intelligence and security committee was in the news recently when Labour's Andrew Little nominated Winston Peters for membership.
Little also proposed expanding the committee to include a Green member by amending the Intelligence and Security Bill currently before Parliament.
In practice, the intelligence and security committee is a toothless watchdog because it doesn't have the powers of a parliamentary select committee.
Select committees have access to all information held by government departments, without exception.
The provisions in the Official Information Act allowing departments to exclude certain information do not apply to select committees.
By contrast, under the new security legislation the head of an intelligence service can withhold from the intelligence and security committee any information he or she determines to be "sensitive".
The definition of "sensitive" is pretty broad, including anything that "would be likely... to prejudice the security or defence of New Zealand or the international relations of the government of New Zealand".
The legislation also specifically allows overseas intelligence agencies to censor what the intelligence and security committee can see. For example, information the US Central Intelligence Agency provides our Security Intelligence Service can be provided to the committee only if the CIA agrees.
Also excluded from the parliamentary committee is any "information about particular operations that have been undertaken" by the Security Intelligence Service or the Government Communications Security Bureau.
Of course, it is generally not necessary for the committee to look at operational details, but it is hard for the committee to be an effective watchdog when it is legally prohibited from seeing anything at all about an operation.
It becomes all too easy for the SIS and GCSB directors to boast about their successes when no one on the parliamentary committee possesses enough information to challenge them.
This is different from the United States where the Senate committee on intelligence has a lot of access to operational information. In December 2014, for example, the Senate committee released a detailed report critical of the harsh interrogation practices of CIA operatives, which amounted to torture.
That US Senate report is relevant to New Zealand, because of the close ties between the CIA and New Zealand intelligence agencies. However, the intelligence and security committee does not have the powers to properly investigate this connection.
Thankfully, the Inspector-General of Intelligence and Security, Cheryl Gwyn, does have such powers and is delving into the matter.
She has announced she is inquiring as to "whether New Zealand's intelligence agencies knew or were otherwise connected with, or risked connection to, the activities discussed in the US Senate report."
Another restraint on the investigative powers of the intelligence and security committee is the fact that it is chaired by the Minister in Charge of National Security, who is the Prime Minister.
The Prime Minister currently also chooses two of the five members of the committee. The Leader of the Opposition also sits on the committee and can choose an additional member.
This is unlike the practice in other parliamentary committees. They are never chaired by the minister in charge of the committee's topic area. For example, the Minister of Health would never chair the health select committee.
Select committees enable Parliament to hold government departments to account. One way they do this is by inviting the minister in charge before them to answer penetrating questions about his or her department's performance.
It is good to have in Cheryl Gwyn a pro-active and inquiring Inspector-General but we also need an effective parliamentary oversight committee with the powers to hold the spy agencies to account. The present legislative constraints on the intelligence and security committee mean it is not up to the job.
It has been operating for 20 years now and has offered not a word of public criticism of the SIS or GCSB. Nor has it helped Parliament and the public become better informed about the activities of our intelligence agencies.
• Keith Locke is a former Green MP.