It is disturbing that more than a decade after East Timor secured its independence, with the assistance of Australian forces, our nations now are in dispute. Primarily, the quarrel is about the division of many billions of dollars of revenue that will flow from developing gasfields in the Timor Sea. Underneath, though, are serious concerns about Australia's conduct during treaty negotiations in 2004.

For years, there has been deep suspicion on East Timor's part that Australian intelligence agencies bugged Timor ministers' offices as they negotiated the Treaty on Certain Maritime Arrangements in the Timor Sea. In May, East Timor declared the treaty invalid, saying Australia had not negotiated in good faith. Arbitration is about to begin in The Hague.

East Timor's case, however, has been disrupted to some extent after ASIO, acting on a warrant issued by Attorney-General George Brandis, raided the Canberra premises of Bernard Collaery, an Australian lawyer acting for the tiny nation. ASIO also raided the premises of a former Australian Secret Intelligence Service officer, who, Mr Collaery says, was prepared to blow the whistle on what happened in 2004.

Our concern for now is the timing of this raid. The Australian government and its intelligence agencies have been on notice about the arbitration for months. They have been aware for years of Timor's allegations about covert surveillance. Yet they left this raid until the last minute. While Senator Brandis contends the raid was not designed to interfere with the arbitration, the fact that it has taken place now invites such suspicions. While we respect the need to maintain certain confidences in the interest of national security, many questions remain unanswered. Security agencies must always exercise their sweeping powers responsibly.

Last month, East Timor Prime Minister Xanana Gusmao chastised "powerful countries [that] shamelessly violate the civil rights... of other countries". He said: "Either we are in the presence of an extreme distrust, where everyone is a potential enemy, or we are witnessing the fraudulent use of technology to obtain economic advantage over others, which is even more immoral when those others are weak and small."

If Australia has exploited such imbalances in power for commercial gain, and done so through espionage, then we should be deeply ashamed.