Actually it gives you plausible culpability, not plausible deniability. This idea that people actually don't get charged/tried/convicted because the evidence is a little flimsy is completely false.

What you say: "I did this cookie thing. I never searched for any sort of kiddie porn on the internet."

What the jury of your peers hears: "Child molester trying to pretend he didn't do it."

What the judge does: Extra time in prison because you aren't taking responsibility for your crimes.

Enjoy your prison sentence.