What constitutes 'depictions of minor engaged in sexually explicit conduct' is far too nuanced and complicated for a discussion on this forum, but it is a class 'B' felony punishable by up to ten years in prison and a $20,000.
That said, RCW 9.68A.070 defines the felony offense of 'Possession of depictions of minor engaged in sexually explicit conduct. and any person engaged in this practice should immediately contact a criminal defense attorney. First, this is far too serious to be discussed on a public forum like AVVO.