Did NASA's James E. Hansen commit perjury when he testified before House Committee on Oversight and Government Reform on March 19, 2007?

Ferenc Miskolczi had previously informed NASA that the equations being used to predict catastrophic global warming were invalid. Yet Hansen told Congress that "greenhouse gases" posed a serious threat.

"The predominance of positive feedbacks, along with the inertia of the oceans and ice sheets, has profound practical implications. It means that if we push the climate system hard enough it can obtain a momentum, it can pass tipping points, such that climate changes continue, out of our control. Unless we begin to slow down the human-made climate forcings, there is the danger that we will create a different planet, one far outside the range that has existed in the course of human history (References 7, 8, 9)."

"It is because of these climate feedbacks and the inertia of the ocean and ice sheets that the global warming problem differs fundamentally from the problem of conventional air pollution (Reference 12). By the time that the public can clearly see the existence of climate change, there is momentum in the system for a great deal of additional change. As a result we are probably already very near, if not beyond, the dangerous level of interference with atmospheric composition. I have discussed the possibility of drawing down atmospheric CO2 by burning biofuels in power plants and capturing and sequestering the CO2 (Reference 13). However, by far the most effective actions at this time would be to slow current emissions to the atmosphere, while better understanding and improved technologies are developed."

My inclination is that he didn't commit perjury even though his statements were inconsistent with Miskolczi's study. The transcript of the testimony doesn't indicate he was testifying under oath. Also other portions of his testimony indicate that agency representatives were expected to provide official explanations even though there might be a question about the accuracy of those statements.

However, I'm not an attorney so I'm not sufficiently familiar with the concept of perjury as it actually applies in a U.S. court of law. I didn't think I. Lewis "Scooter" Libby should have been prosecuted for perjury.

Someone who is familiar with the law regarding perjury needs to investigate the situation to determine if Hansen violated the law.