Walton, selected by the Bengals in the fourth round of the 2018 NFL Draft out of Miami, was arrested on three separate occasions in three months this year. Cincinnati eventually released the tailback this off-season.
Dolphins head coach Brian Flores, who offered a tryout to Walton over the weekend, said the embattled running back deserved a second chance.
"I don't want to judge people based on one incident [or] two incidents," Flores told reporters. "I think it's a case-by-case situation for a player and just for people in general. That's kind of my stance."
Walton is facing a felony charge for carrying a concealed weapon, along with three misdemeanor charges of resisting an officer without violence, marijuana possession and reckless driving, according to ESPN. The legal matters from his arrests on Jan. 16, Feb. 16 and March 12 are still pending, and he could face potential discipline from the league.
Walton joins Kenyan Drake, Kalen Ballage and Kenneth Farrow on the Dolphins' current roster. Miami also drafted fullback Chandler Cox and running back Myles Gaskin in the seventh round of the draft.
Walton had 14 carries for 34 yards, and five receptions for 41 yards in 14 games for the Bengals last season.