Labor Senator Doug Cameron was last night forced to adjourn a heated estimates hearing with NBN Co chief Mike Quigley after proceedings descended into a slanging match between participants.

Quigley had started the proceedings with a lengthy statement on the Alcatel-Lucent bribery scandal, a topic the Coalition had flagged it would use estimates to pursue.
The statement did little to placate Coalition senators who extensively quizzed Quigley on the scandal, and on how much taxpayer money was used to prepare Quigley's opening statements.
"I deeply regret public money being spent on this issue but I have no choice but top employ people if we're going to have a retrial of the five-year investigation [in the United States here]," Quigley said.
"I have no choice now but to check every fact and to do that I have to go through every document [from the case]."
Queensland Liberal Senator Ian Macdonald repeatedly sought information on the amount NBN Co "expended on external lawyers", the names of the lawyers "and the cost [of NBN Co's] own internal lawyers" to prepare Quigley's opening statements.
"So [you want] the cost of preparing the information provided to the Senate?" Communications Minister Stephen Conroy interjected.
Macdonald said proceedings were "turning into a farce". Conroy said it already "was a farce".
More slanging followed in which Macdonald branded Conroy a "moron". The committee chair Doug Cameron was forced to temporarily halt proceedings, after warnings to do so were shouted down.
"There has to be some order with the way we deal with this [matter in] committee," he said.
"If I'm being ignored I'm not prepared to continue. There is an obligation on all Senators including the Minister to try and get on with this."
Later, Senator Simon Birmingham attempted to extract an admission that Quigley had "unthinkingly" or "unknowingly" signed off on fraudulent arrangements in his time at Alcatel.
The question was eventually taken on notice.
Questions from Greens Senator Scott Ludlam were among the few asked on a subject other than Alcatel-Lucent's bribery scandal.