Schofield played 2013 with the Seahawks, with just seven tackles and one sack. His previous three seasons were spent with the Cardinals, where he had 10.5 sacks total.
Over his career, he has 78 total tackles, 11.5 sacks, four forced fumbles and one fumble recovery.
The Giants do need some depth at LB and the "joker" position, which Schofiled may be being brought in to play. The choice is a curious one otherwise. He's certainly isn't being signed in lieu of Jon Beason.
My take is that Schofield has been on the Giants' radar since his days at Wisconsin where he was a top player: Schofield was a 2nd Team All-American and an All Big 10 selection in 2009. He finished second in tackles for a loss and QB sacks in the Big 10 that season and would go on to be the defensive MVP at the East-West Shrine Game.
He tore his ACL during Senior Bowl week and was drafted by the Arizona Cardinals in the fourth round of the NFL Draft in April 2010.