Here is a quick link... I can’t remember all the details..
Former Sandia and Los Alamos laboratory employee Peter Lee (no relation to Wen Ho Lee) gave top secret information on antisubmarine radar technology away to Chinese nuclear-weapons experts during a May 11 lecture at the Institute of Applied Physics and Computational Mathematics in Beijing, China. Lee pleaded guilty to filing a false statement about his 1997 trip to China and to giving classified laser data to Chinese scientists during an earlier trip to China in 1985.[16]
https://en.wikipedia.org/wiki/Timeline_of_the_Cox_Report_controversy
Peter Lee had previously passed a working klystron switch to the PLA enabling them to miniaturize thermonuclear weapons - this was free to prove Clinton’s ‘good faith’.
Clinton was all about selling the latest tech to the Chinese under his Third Way philosophy which (in part) states that if two parties have military parity, neither will use it. So he was just getting the Chinese up to speed ... and some cash in his pocket.
All of that was the basis for the impeachment actions, but despite the mountains of evidence, our wonder-filled Congressional ‘leaders’ saw fit not to read any of it. So they went with the blue dress - rather than remove Clinton under treason charges. I believe that there must be a declared enemy to mount such charges, and there were none, so it would have been a difficult case, perhaps with no removal in the end.