The 21-year-old midfielder hit the headlines in August 2012 after being found by police in possession of an ecstasy tablet on Melbourne's King Street.
Liberatore received a strike under the AFL's illicit drugs policy and was suspended by the club for the rest of the season.
In 2013, Liberatore has emerged as an elite midfielder and the club's faith in him has been restored, signing him to a new three-year deal on Thursday.
"Tommy doesn’t say much, but the events of 12 months ago left a lasting impression," McCartney said.
"It's all part of growing up and maturing, as a club too [with] how we deal with it and [how] we develop our people and players [while] still respecting they are all unique individuals and have different character traits."
He leads the AFL in clearances and centre clearances this year and is ranked among the AFL leaders in terms of long kicking efficiency and is now the 49th ranked player in the AFL according the Official AFL Player Ratings.
Meanwhile, the Bulldogs are poised to recall Liam Jones for Saturday's clash with Carlton after the forward missed the club's loss to the Sydney Swans with an ankle issue.
Adam Cooney was a noticeable absentee from Thursday's training session, but was spotted training away from the group.
Matthew Boyd is facing a race against time to overcome a calf complaint in time.
"We'll know more today, we'll put him through half testing half training," McCartney said of Boyd.
"Any risk we won't [play him]. If he's right to go he'll play. It would be good to have him back."
McCartney insisted Boyd's inclusion would not automatically cost Daniel Cross his spot in the side.
"Its not as simple as that," McCartney said.
"People are quick to jump to that. We've picked a team all year, one to deal with the opposition in front of us, and two, to make sure we're developing our players. But they are earning a game and giving us output."
Boyd and Cross have played just five gamest together this season, with the last being in the club's round eight clash against Gold Coast.
