A ex-Purdue University student will serve the first 90 days of his four-year prison sentence behind bars after being sentenced last week for hacking into his professor's computers and changing his grades.

Roy Sun, 25, scored a $70,000 per year job fresh out of undergrad, but returned to Massachusetts to pursue a master's degree. That was working out for him until it was revealed that he had schemed his way through Purdue, beginning in 2008 when he altered his first grade using a keystroke recorder:

Sun first hacked into a professor’s computer account and changed his grade in 2008. He said he volunteered to be the guinea pig to see if he and fellow Purdue student Mitsutoashi Shirasaki would get caught. They didn’t, which emboldened Sun.

“When I came back in 2009, I felt really arrogant,” he said during the sentencing hearing. “I thought I was untouchable.

“It became so much easier to change my grades than going to class and working real hard.”

So with the exception of one course, Sun quit attending classes his senior year and still received straight A’s.

Eventually, Sun and Mitsutoashi Shirasaki grew cocky, hacking into professor's computers roughly 10 minutes before they submitted final grades to change them. They even changed the grade of a friend, Sujay Sharma's grade, without him even knowing. 

Both Sun and Sharma pleaded guilty on Dec. 30, with Sun facing more severe charges including computer tampering and conspiracy to commit computer tampering for admitting to being the mastermind. Sharma was given 18  months of probation for serving as a lookout for Sun and Shirasaki, as well as pleading guilty to a count of conspiracy to commit computer tampering. Shirasaki fled to his native Japan at Sun's urging. 

Sun's life was in shambles prior to his sentencing. In addition to being stripped of his bachelor's degree, he was expelled from Boston University and had been somehow subsisting as a part-time busboy who made roughly $1,500 last year. 

After serving his 90 day sentence, Sun will complete the remainder of his sentence under supervised probation.

[via Gawker and Lafayette Journal & Courier]