Eric Yee, 21, a former Yale student, is charged with possession of an illegal weapon but may face more charges.
Yee is suspected of going on ESPN's website and posting that he was watching children and wouldn't mind killing them. Police said several unregistered weapons were found when Yee was arrested at his parents' Valencia home, which overlooks two schools. His father, Roger Manfoo Yee, 62, is also facing weapons charges.
Some of the nearly 3,000 reader comments on the ESPN website talked about children possibly getting killed over the expensive, new Nike sneakers named after LeBron James. ESPN is based in Connecticut, where a worker told police about Eric Yee's online threat posting.
Yee's lawyer, David Wallin, said Yee was simply trying to give his social and political commentary on shoes that cost $270 and was paraphrasing from the movie "American Psycho."
Yee's bail has been reduced from $1 million to $100,000. It wasn't immediately clear if prosecutors would still pursue the threat allegation. His arraignment was postponed to Oct. 16.
The Associated Press contributed to this report.