"We'd love Reuben to be on this team," he told NBC Sports Bay Area (h/t ESPN.com). "And we'd love him to participate for us, but if he's not doing things off the field that allow us to be able to rely on him—or he's doing something that we're not comfortable with off the field and it's proven that's what's going on—I think the guys have said then you're just going to have to move on."
Per that report, Foster was arrested Feb. 11 after suspicions of "domestic violence, threats and possession of an assault weapon." The Santa Clara County District Attorney's office is still determining whether to press charges and pursue the case.
"Any time there's an issue like that, we'll have a discussion," York added. "Right now, there's still a lot of work that needs to be done with Reuben. And we'll handle that as it comes. You don't want to say it's easier outside of the season, but it is easier outside of the season because you don't need to make a decision today.
"We have to wait until that (a decision from the Santa Clara County DA's office) happens, but that will obviously be something that we get together and discuss whatever comes down when those issues come up and figure out where we move from there."
Foster was also arrested and charged with misdemeanor marijuana possession in January. And he raised eyebrows last year when he was sent home from the NFL Scouting Combine following an argument with a hospital worker. He also gave a diluted urine sample at the combine, which counts as a failed test in the NFL and led to him starting his career in the league's substance abuse program.
Add it all up, and the second-year linebacker is standing on thin ice.
"From my conversations with John and Kyle, I know Reuben is very cognizant of where his position is right now, and his time with the 49ers could potentially be over if he continues to do things outside of the team that aren't what we want him to be a part of," York noted.
Foster, 23, had a solid rookie season, registering 72 tackles in 10 games, though ankle and rib injuries cost him six games.
He was expected to become the next stalwart linebacker for the Niners after years of elite play at the position from players like Patrick Willis and NaVorro Bowman, though his future in San Francisco has become cloudier given his potential legal troubles.