If they can't show overwhelming evidence of post Gulf War '91 WMD weapons, materials, programs, research, etc. then they just quietly ignore these things as they are found.
Never mind whether it was illegal or had been hidden but people just see it was obtained in the 80's or what have you and laugh it off.
Huh?
That would be like having the police get a warrant for you having illegal firearms, knowing you have a legal gun (registered, even!)...and then after they knock down your door and find no other gun, they say, "See! He has a gun!" while they point to your only one.
These materials obtained in the '80s can't be used to kill people? So they aren't relevant? Wonder why Saddam didn't use them in the war, but thank God they weren't.