Google is not a "rational business" according to its chairman Eric Schmidt.

While Google's CEO Larry Page was duking it out with Oracle's Larry Ellison over Android, Eric Schmidt was giving evidence in a Senate antitrust panel. In his testimony, Schmidt had to answer whether Google could be an unbiased search engine and still own a number of web properties.

Schmidt answered that question by saying, "I'm not sure Google is a rational business trying to maximize its own profits." On the face of it there is some evidence to support that claim.

After all, Google has invested millions in developing its Android operating system yet gives it away to handset makers for nothing. The same could be said about its email and Google Docs services, but dig a bit deeper and you see that almost everything Google does is to maximise its ability to sell advertising.

However Schmidt wasn't let off that easily, with Senator Mike Lee, Republican of Utah, pointing to some search results in which he claimed "You cooked it so you are always number three." Schmidt fired back, saying, "Senator, I can assure we haven't cooked anything."

Schmidt didn't refer to Microsoft by name during his testimony but made references to a previous technology company that was found to have broken US antitrust laws. Some might suspect that Schmidt was referring to Microsoft when he said, "We get the lessons of our predecessors," adding, "One company's past needn't be another's future."

Google is being investigated on allegations that it favours its own web properties over competitors' when it comes to search results. Due to the dominant position Google has in the search market, it is thought that any bias shown by Google could effectively steer the market.