He’ll get to the rest and relaxation part of his offseason eventually, but Detroit Lions running back Bo Scarbrough has some unfinished business to take care of first.

Scarbrough, who shined in six late-season games for the Lions after signing to the practice squad in early November, is going back to school this winter to finish up a degree in criminal justice that he’s 14 credit hours shy of completing.

The University of Alabama started its spring semester Wednesday, and Scarbough said he’s enrolled in three classes: a statistics course and two criminal justice classes.

He plans to finish up his degree with one final elective over the summer and graduate in August, just after the start of training camp.

“Hell, yeah, I’m gonna walk,” Scarbrough said in late December before the Lions’ final game against the Green Bay Packers. “I got to go back and do that.”

For Scarbrough, the desire to graduate isn’t born out of a promise to family to get his degree, but rather a long-standing mission to become an FBI agent when his football career is done.

“You know when you’re a kid and they be like, ‘Write down what you want to be when you grow up.’ and most kids always put police officer or firefighter or that,” Scarbrough said. “I wanted to be an FBI agent investigator because I like to investigate things. I like to know what happened. If I don’t know what happened, it kills me, eats me up on the inside.”

Scarbrough enrolled at Alabama in January of 2015 and left school with one season of eligibility remaining.

He was a seventh-round pick of the Dallas Cowboys in 2018, and spent time with the Jacksonville Jaguars and Seattle Seahawks before signing with the Lions on Nov. 6.

[ Why the Lions might have found their running back tandem of the future ]

While finding his footing in the NFL has been Scarbrough’s focus for most of the past year – he didn’t appear in a game until the Lions promoted him to the active roster Nov. 16 – he said there are practical reasons to go back and finish school now.

First, as he’s already learned playing for four teams in the past 15 months, “football is not a career.”

“It’s something temporary, so you can’t play forever,” Scarbrough said. “Someday, somebody will say that it’s time for you to let it go and I got to be able to fall back on something to keep my expenses going and being able to take care of my family. I’ve got to be a professional at something else.”

Second, the timing works out. The Lions don’t return for voluntary offseason workouts until mid-April. Alabama’s spring semester ends April 24, with final exams the next week, so Scarbrough should be able to both complete his classes and attend the Lions’ offseason program.

And third, “I get to work out for free” at Alabama’s football building and with the team’s strength staff while on campus.

“I don’t have to pay no one to train,” Scarbrough said. “But the most important thing is that I got to get that piece of paper.”

With the Lions, Scarbrough played well enough in his late-season cameo that he should be a part of the team’s backfield going forward.

He’s a bruising runner at 6 feet 1 and 228 pounds, and he and Kerryon Johnson proved an effective tandem when Johnson returned from injured reserve for the final two games of the season.

More Roll Tide? Tua Tagovailoa declares for NFL draft; what it means for the Lions

Scarbrough finished with 377 yards rushing and one touchdown in six games, and had back-to-back 98- and 83-yard rushing performances in November, the Lions second- and third-best individual outings of the year.

He said spending another semester in college will “be fun,” and he said he'll treat the next few months just like he did when he was playing for the Tide: "Go to class, then go work out, then take care of my body."

“I’m the type of person that if I start something I have to finish it,” Scarbrough said. “I wouldn’t even feel right to start it then (not) finish it. It’s like unfinished business. Like you can’t start an interview and then stop it. And I’m my mom’s only child, so I want her to have something, I want her to be proud of something that I did, that I accomplished in life that most people don’t get the chance to go do. Not because they played a sport or anything, because some people don’t have the financial (means) to do it. I know my mom don’t have the financial (means) to do it, but I got a chance to get a free degree.”

Contact Dave Birkett at dbirkett@freepress.com. Follow him on Twitter @davebirkett. Read more on the Detroit Lions and sign up for our Lions newsletter.