In a lengthy mea culpa released late Sunday night, Shemy admitted to being "flippant" on the social media app ... after people had found he had "liked" multiple tweets that were insensitive -- and downright racist.

Some of the tweets that Shemy had put a heart on included ones that suggested Jim Crow laws benefitted Black people.

"By inexplicably and irresponsibly liking things on social media I owe an unabashed and unequivocal apology to my hundreds of friends and fellow coaches in the Black community, all communities, the University of Michigan, my father's legacy and my family," Shemy wrote in his apology statement.

"Any words or philosophies that in any way seek to underplay the immeasurable suffering and long-term economic and social inequities that hundreds of years of slavery and the 'Jim Crow' era caused for Black Americans is wrong."

"I was wrong," he continued. "We must never sanitize morally unsanitary, historical behaviors that have hindered the Black community, or any other community. There are no historical silver linings for the experience of our brothers and sisters."

Shemy had been hired by UM on Wednesday to be its assistant director of football recruiting. But, on Saturday, Jim Harbaugh and athletic director Warde Manuel announced he'd no longer be in that role.

"We are aware of some comments and likes on social media that have caused concern and pain for individuals in our community," the two said in a joint statement. "Michigan Athletics is fully committed to a place where our coaches, staff and student-athletes feel welcome and where we fully support the University’s and Athletic Department’s commitment to diversity, equity and inclusion."

Shemy's Twitter account is now deactivated.