“How is it possible to even imagine that Google could get the consent of people who appear in videos put online?” Mr. Vaciago said after the hearing, which was held behind closed doors. “How could the company check if consent has been given? Whoever uploads the video has to ask for the consent of those in the video. This is a rule that applies to all video platforms on the Internet.”

The prosecutors rested their case last month after asking for a one-year sentence for three executives — David Drummond, senior vice president and chief legal officer; Peter Fleischer, global privacy counsel; and George Reyes, a former chief financial officer. Prosecutors are seeking a six-month sentence for Arvind Desikan, who is now head of consumer marketing for Google in Britain.

If found guilty, the four defendants, none of whom have appeared in court since the trial began this year, would not serve time in jail because sentences of less than three years are commuted in Italy for those without a criminal record.

Mr. Vaciago and another lawyer for Google will finish their arguments in front of the judge Dec. 23. The prosecutors will then have a chance to respond Jan. 27. If only a limited amount of new material is presented, a ruling could come that day or soon after.

While Mr. Vaciago said he concentrated on addressing the question of the consent of those appearing in the videos, he said he would address the crux of the accusation at the next court appearance — that Google either knew the video was up and did nothing to take it down immediately or showed negligence even if it did not know.