Because he violated New York State's Indentity Theft law when he used stolen identities and forged email addresses to send out 825 million bulk emails, "Buffalo Spammer" Howard Carmack has been sentenced to 3.5 to 7 years in prison.
If he behaves in prison, he will only stay there for 3.5 years. Postini Inc. estimates that about 83% of all email messages are spam. Last year EarthLink won $16.5 million in a lawsuit against Carmack.
In this instance Carmack was charged with 14 counts of forgery and identity theft and he got the maximum sentence for these crimes. Source