Is it a lawyer's professional responsibility to withhold or conceal the instrumentalities of a crime?

In People v. Lee (1970) 3 Cal.App.3d 514, 526, 83 Cal.Rptr. 715 ⁸ the court stated it was " 'an abuse of a lawyer's professional responsibility knowingly to take possession of and secrete the instrumentalities of a [24 Cal.App.4th 1019] crime.' " Its discussion made clear the responsibility extended to other physical evidence. (Ibid.) Defense counsel could withhold the physical evidence for a reasonable time to examine it but then " 'should, as an officer of the court, on his own motion turn the same over to the prosecution.' " (Ibid.)