They did do the journalism with respect to the jurisdiction issue. The Secret Service has jurisdiction in 'computer crimes' and 'access device fraud' via USC 18 S. 3056.
Not sure about the details there, and wikipedia is silent. Certainly SJG employees were active in the phreaking community. But AFAIK none were ever charged with anything. And I know with certainty no charges resulted from this raid in particular.
The whole thing was a terribly botched job, the "facts" in the warrant were a mash of giant whoppers of technobabble. It was a mess.
Did the SS have the best interests of society at heart, and might they have reasonably been fooled into thinking something was up at SJG? Yeah, probably. Did they actually do the right thing? No way.
Why was a Secret Service Agent on campus in the first place?
Something is just not adding up as FBI has jurisdiction not Secret Service..
Plus, what is the other 2% that was downloaded that was not JSTROR stuff?
Or ie ah do some journalism before writing the article?