The only real legal point you have is the hints and threats issue. There isn't a good public record of what was said. From the article, it appears as though he

The only real legal point you have is the hints and threats issue. There isn't a good public record of what was said. From the article, it appears as though he said he wasn't going to publish names publicly. Although, it seems to suggest this was post DDOS. There isn't a clear enough public documentation of what happened to fully say one way or another. My suspicion is that those on the list did not tell him to stop, which is one way legally of measuring when harassment starts.