The 45-year old Tumpkin had been on Colorado's football coaching staff since February of 2015. He served as the safeties coach for two seasons, and was the interim defensive coordinator for the Alamo Bowl in December after Jim Leavitt left for Oregon.
Earlier this month, George and head coach Mike MacIntyre learned that a judge had issued a temporary restraining order against Tumpkin at the request of his ex-girlfriend. Tumpkin was immediately placed on administrative leave from the University.
"Joe is currently defending himself against allegations made in court records that do not represent our values,” George said. “Furthermore, we need to move forward to ensure we do not have gaps in our coaching staff as we build the team and sign new recruits.”
In consideration for his resignation, Tumpkin will receive two months of severance pay, which equals $34,000.
DJ Eliot was named Colorado's new defensive coordinator and linebackers coach last week but now with Tumpkin's departure being made official, the Buffaloes have two assistant coaching openings. Colorado is close to filling at least one of those vacancies, sources have indicated to BuffStampede.com.