The client admits to have viewed the illegal content, is he still at fall?

Saying sorry doesn't make it better. Speaking of admitting to wrongdoing, I'm sure your teach would get out the ruler if she knew you were asking questions on .

Generally, you have to have possession in order to view it. Probably can be prosecuted unless he viewed in by mistake and can prove it.

I don't know how much you've received from your teacher by way of resources. Here's a link to the statute: http://www.leginfo.ca.gov/cgi-bin/displaycode?section=pen&group=00001-01000&file=311-312.7 Here's a link to the jury instructions, under item "C" (what the prosecutors must prove): https://www.justia.com/criminal/docs/calcrim/1000/ Here's a link to Google Scholar, where you can look up what judges have said about crimes in previous cases: https://scholar.google.com/ That should be all you need. Good luck!

Sounds like you've identified your defense. Do your own homework.

But in order to view, he would necessarily have to possess, would he not? You have to look beyond the "all he did" mentality when assessing criminal liability. The question then becomes whether or not they could prove the case if there is no actual evidence of possession aside from the defendant's statement admitting to viewing. That is the "corpus rule" (from corpus delecti)

The defense in a criminal case does not need to prove innocence, only that there is a reasonable doubt.