Indra Thappa, who was disciplined over allegations that he bullied a colleague and was rude and aggressive to an outside consultant, says he has not worked for more than four years after the agency's processes left him with an ''adjustment disorder''.

But the Administrative Appeals Tribunal has backed AusAID bosses in their treatment of Mr Thappa, finding that he was treated reasonably by the overseas aid agency and that he was not entitled to compensation.

AusAID has been the subject of allegations, which it denies, by federal Coalition politicians that the agency has a culture of bullying and harassment but the tribunal says it acted properly in dealing with Mr Thappa's alleged misconduct.

The official's troubles began when he was assigned to a team evaluating a road-building project in a remote region in Papua New Guinea and he clashed with an academic expert who had also been drafted in to help assess the project. Mr Thappa was accused of ''behaving inappropriately, raising his voice aggressively and making derogatory remarks about AusAID personnel''.

In response, his superiors reminded Mr Thappa of his responsibilities under the APS Code of Conduct and he resigned from the evaluation team.

Several months later, in 2009, Mr Thappa's supervisor, Janet Donnelly, alleged she was being bullied by her subordinate.

He was ordered to undergo counselling but after just one session, in February 2009, he left work and has not returned.

In his claim to federal workplace insurer Comcare, the APS6 level bureaucrat said he suffers adjustment disorder, anxiety and depression caused by his treatment at the hands of AusAID.

After his claim was rejected, he appealed unsuccessfully to the Director-General of AusAID, the Public Service Merit Protection Commissioner and the Commonwealth Ombudsman before taking his case to the tribunal.

Mr Thappa argued he had been denied procedural fairness, natural justice and that his superiors were biased against him.

Tribunal member Simon Webb rejected those arguments, finding that AusAID acted reasonably towards its employee while trying to manage his behaviour towards his fellow workers.

''Mr Thappa's assertion that these managers, in some way, colluded or conspired against him is not supported by evidence, and it is not consistent with the documents in evidence,'' Mr Webb wrote in his decision. ''The evidence establishes that concerns about Mr Thappa's performance were documented over a long period, from July 2008.''