No, it was most definitely not illegal. That was made abundantly clear in the hearing today.
There were two sets of input data. One was purely public domain, readily available info purchased from a private corporation.
The other set was a combination of that info and classified info. That data was only handled by intel people, whereas the other set (pubic info only) was handled by both intel people and private contractors.
Data mining itself is not illegal. The debate today largely centered around the relationship of data mining to Posse Comitatus, and there was no testimony brought forth that suggested a violation of law.
No testimony "brought forth." Did they ask the right questinos?
"Intel people"
Were those "Intel people" "intel people" associated with military intelligence branches?
Illegal. And I bet the "wall" between private and "intel" was not as strong as Gorelick's.