A senior bureaucrat with the Finance department sent out a mass email across government asking organizations to retweet messages about the announcement using the hashtag #StrongFamilies.
"We ask that your organization re-tweet the Department of Finance tweets from @financecanada on the announcement over the following 72 hours," wrote Jean-Michel Catta, an assistant deputy minister.
"Most of our tweets will contain the hashtags #StrongFamilies ou #Famillesfortes."
The proposal, which includes income splitting for families with children under 18 and extending the monthly Universal Child Care Benefit to more taxpayers, has not yet received parliamentary approval.
Both the NDP and the Liberals have been sharply critical of the income-splitting plan, which they say will benefit only 15 per cent of Canadian families.
Liberal finance critic Scott Brison argues the tweets are partisan, and shouldn't be promoted by public servants. The government is again spending money to advertise the proposal on TV and radio, even before it is voted on, he noted.
"It shows again that the Conservatives don't understand the principle of a professional public service separated from partisan politics," Brison said.
One individual tweeted back at the department, asking, "Since when are you an arm of the CPC advertising group?"
Finance spokesman David Barnabe said the directive was sent to departmental heads of communication "for use with their official social media channels, which is common practice to broaden government messaging."
Harper used the phrase "strong families" during the 2011 election campaign when he first promised the measures, and then again during a partisan speech to Conservatives this summer in Calgary.
Several government departments retweeted the information and hashtag about Harper's measures, including Aboriginal Affairs, Natural Resources, Health Canada and Agriculture.
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