During his cross examination he said the matter of regulation A19 was only discussed during an item called "workforce change" - one of 11 items on the agenda.

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Indeed, I pointed out when he idea was first being discussed that there are only 5 or 6 plants globally capable to turning the mineral, coltan, into tantalum.

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But White House Counsel Charles Ruff had filed an affidavit in federal court before Judge Johnson only seven days earlier in which he swore that he had discussed the assertion of executive privilege with the president and that the president had approved its invocation.

CNN: Transcript: Judiciary Committee impeachment hearing