Here you go, generally regarded as the first hacker ever arrested[1], though the preferred term is phreak, I think phreaks are technically a subset of hackers.
Draper was definitely not first hacker ever arrested, but perhaps "first hacker sentenced to prison." (Ralph Barclay, inventor of the blue box used for phone phreaking, was arrested in 1961 or so, almost a decade before Draper came on scene. When I interviewed him I said, "You were the first!" He laughed and responded, "Well, first to get caught, maybe.") http://explodingthephone.com/docs/dbx0575.pdf or more generally http://explodingthephone.com/search.php?q=barclay&sort=relev...
[1] https://en.wikipedia.org/wiki/John_Draper