Microsoft stumbled in its defence of anti-trust allegations by the US Department of Justice on Tuesday after an embarrassing blunder over a piece of videotaped evidence.
The software giant took videotaped evidence to court to demonstrate that its Internet Explorer browser is an integral part of Windows and that it did not simply bundle it with Windows to steal market share from rival browser maker Netscape.
US government witness Edward Felten, a computer scientist at Princeton University, earlier in the trial showed using a piece of software that blocks Internet Explorer, that Windows functions normally without Explorer.
But Microsoft said the tape showed its engineers demonstrating "performance degradation" of Windows after blocking Explorer with Felten's program. The video showed Microsoft's separated browser taking an "unusually long time" to access a web site.
However, as Microsoft witness James Allchin, senior vice president in charge of Windows showed the tape, the court quickly spotted that the system on the tape didn't appear to be using Felten's program after all.
"This video that you brought in here is a video that purports to show a performance degradation, and that's just wrong, right?" US Department of Justice lead attorney David Boies asked Allchin, "How in the world could your people have run this program calling it the 'Felten program,' when they knew it was not?"
But despite the demonstration appearing wrong, Allchin said it was a bone fide demonstration.
"The performance problem exists. I apparently didn't check the title bar close enough. But I personally tested this and I know it to be a fact," he said.
Boies paused at this remark and asked: "Mr Allchin, you do understand that you came in here and you swore this was accurate?"
"To the best of my ability," replied Allchin.
"You know it does matter whether what you said is right or wrong - you know that matters, don't you?" Boise said.
"What's on the screen is the truth," Allchin responded.
Later, Microsoft general council William Neukom backed up Allchin, telling reporters that while Windows code had made it appear that the Felten program was not running, it in fact was. "What you saw on the tape, and what the court saw, was a machine disabled by the Felten program," said Neukom.
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