Emails obtained by The Canadian Press show that in May, MacKay saluted mothers in the department for holding down two full-time jobs — at home and at work.
"By the time many of you have arrived at the office in the morning, you’ve already changed diapers, packed lunches, run after school buses, dropped kids off at daycare, taken care of an aging loved one and maybe even thought about dinner," MacKay said of the moms in a staff-wide memo that went out to thousands of employees before Mother's Day.
The email didn't get much reaction internally until the Father's Day version arrived a month later.
It made no mention of any household duties, but said the men were "shaping the minds and futures of the next generation of leaders."
"... Needless to say, it can also be daunting to consider the immense and life-long influence we have over our children," MacKay wrote. "Our words, actions and examples greatly mould who they will become.
"We can only hope that the moments we spend teaching, guiding and loving them will sustain them throughout their lives."
The Mother's Day message does not touch on the impact the women have on their children's futures. In both instances, MacKay referred to the fact that he is the father of a toddler.
MacKay's office did not respond to a request for an interview or to take questions by phone.
"With regards to the messages to Department of Justice staff, the minister takes every opportunity to thank the staff for their contribution to the department and to advancing justice issues on behalf of all Canadians," spokesperson Paloma Aguilar said in an email.
The Mother's and Father's Day messages MacKay co-signed with junior minister Kerry-Lynne Findlay from the Department of National Defence in 2013 did not include any personal references.
In May, they wrote, "We pay tribute to the women who share so many important moments with us, shaping our lives and society."
And in June, dads were described as "heroes."
"Fathers who serve in the Canadian Armed Forces are not only the protectors of their family but also the protectors of our great nation and its interests."
Liberal trade critic Chrystia Freeland calls the difference in the Justice Department email messages striking and says they play on outdated stereotypes of parental roles.
"I think that particularly in families like the ones that were addressed by these emails ... I simply don't think that reflects the modern Canadian family and is demeaning to both mothers and fathers," said Freeland.
"Both mothers and fathers change diapers and worry about dinner and both mothers and fathers, at least we try to mould the minds of our children and to set an example through our own actions."
MacKay has faced criticism recently over comments he made on the roles of parents in the context of the dearth of female judges in Canada.
"At early childhood, there's no question I think that women have a greater bond with their children," he said Thursday.
The Toronto Star reported last week that MacKay rankled a group of Ontario lawyers during a private meeting when he said that women weren't applying for judge jobs.
The Star, quoting lawyers at the meeting, said MacKay suggested that women didn't want to join the bench because they feared being sent out travelling on a circuit court.
On Sunday, MacKay took to Facebook to say that he did not make the comments attributed to him.
"These allegations are simply untrue and in fact the opposite of everything that I said," MacKay wrote.
"Rather, in addressing a few dozen lawyers I took the opportunity to encourage MORE women and minorities to apply to be judges, to enable the federal government to promote them to the bench and thus to better reflect the diversity that is Canada today. That was the intent and tone of my remarks."
Jenn Gearey, a member of MacKay's staff on maternity leave, tweeted Tuesday that the criticism of the minister's emails was "ridiculous," noting his chief of staff, director of communications and director of regional operations are all women.
Gender issues are always a factor in electoral politics. Liberal Leader Justin Trudeau has tried to stake territory with women voters by announcing all his candidates must commit to vote pro-choice on matters touching on abortion in the Commons.
The Conservatives, meanwhile, have promised to introduce income-splitting for families. The plan would allow a family where one spouse makes much less than the other to pool earnings to reduce taxable income.
The party's base includes many social conservatives who strongly support such a proposal, arguing it removes tax discrimination against families and would provide more economic flexibility to parents.
"Each family embraces their personal responsibilities and the challenges in their own way and I respect that," MacKay said in his Facebook post.
"Again, this reflects the fabric that is our country and that is something we all value and share."
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