Evans, a cornerback, missed the entire 2011 season due to an injury, allowing him one final year of eligibility, which can be used in 2012.
"I am extremely excited about the opportunity to finish my college football and academic careers at Northwestern," Evans said in a statement. "My visit to campus and the relationships I've developed with Coach Fitzgerald and other members of the Northwestern football program have left no doubt that NU is the right fit for me at this time. I'm looking forward to meeting my new teammates at the start of camp and contributing any way I can to our success this season."
Evans is a native of Chandler, AZ, who graduated from Basha High School. He will earn a degree in sociology from Stanford this month, and is pursuing a masters degree in Northwestern's School of Continuing Studies.
In his Stanford career, Evans played in 20 games, mainly serving on special teams. He recorded 13 tackles with the Cardinal.