But as the Packers completed the first day of their three-day mandatory minicamp Tuesday, McCarthy acknowledged that he still isn't sure what level of contact can trigger a violation.
"Frankly, I don't know what the line is," McCarthy said.
Last week, the NFL punished the Seattle Seahawks after the league's management council and the players' union determined that Seattle violated the collective bargaining agreement's offseason workout rules by having live contact during organized team activity sessions.
The Seahawks had to forfeit a pair of scheduled OTA practices, plus a workout day.
The new CBA says teams are not allowed to hold live contact drills or have players wear pads during OTAs or minicamps; teams are allowed to have players wear helmets.
Offseason contact also was banned under the previous CBA. But given the current emphasis on player safety, the Seahawks' punishment may be a sign that the ban will be policed more strictly. Teams now must film all on-field offseason activities, retain them until 30 days after the start of the regular season and make them available to NFL Players Association officials in the event of a dispute.
Veteran center Jeff Saturday, a member of the NFLPA executive committee, acknowledged that policing offseason contact is a gray area.
"I think it's been difficult for all of us," said Saturday, who signed with the Packers in the offseason. "When it's written in legalese, it's totally different than what you do on the field. It's very hard to know what is crossing the line, what's too much, what's too little. I think you kind of put coaches out in an area where it's very uncomfortable for those guys, and for a guy like me it's very uncomfortable, because I have guys coming to me, asking me, you don't really know a definitive answer. So we're trying to figure it out."
In general, Saturday said, when two players do make contact on the field during an offseason practice, they should disengage.
"And for football players, when you put the helmet on, it's tough to control that," Saturday said. "You get in this competitive mode, so from our standpoint, we've got to learn to limit the competition to protect our guys. You know, we're all going to be one team here shortly, and we've got a long road to hoe, so we've got to make sure we're taking care of our guys."
Saturday said the players are relying on NFLPA officials to help enforce restriction on contact.
"They need to draw the line and let the coaches know, ‘Hey, this is enough, this is too much, you can go up to here,' so everybody is clear," Saturday said. "And I think the PA now, they're taking trips, they're getting on people's practice fields to really be able to give those coaches feedback of what we're doing right and what we need to improve."
Follow Associated Press writer Chris Jenkins on Twitter at twitter.com/ByChrisJenkins.