He called for the DEC to improve accountability by publishing member agencies' internal progress reports to the DEC secretariat and allowing them to be publicly audited. "It might give a more independent and objective view," he said.
An unpublished version of this year's evaluation of the DEC agencies' response to the Asian tsunami was leaked to the BBC's Newsnight. The official DEC report, published the next day, was shorter and some strong rebukes had been replaced with milder criticism.
Jacobs said DEC board members always saw a draft of the evaluation prior to publication. "They may have a better understanding of the range of its work, so they have an important corrective role to play," he said.
"But they may also naturally want to reduce public criticism of their work. They often seem to want to tone down the language."
He added that the tsunami report team had not had enough time to assess the relief effort.
Brendan Gormley, chief executive of the DEC, said the evaluations were "genuinely independent". He said: "A first draft is circulated to DEC members so they can suggest corrections. However, the consultants have complete control over what is and is not included."