Should questionable social media posts automatically spell disaster if someone wants to run for office? 

Stephen McNeil doesn't think so.

The Nova Scotia Liberal leader knows a thing or two about the issue as the province nears a May 30 vote. His party dropped Pictou East candidate Matt MacKnight during this provincial election campaign when offensive tweets MacKnight wrote several years ago were brought to light. McNeil said part of the problem is when campaigns and parties find out about past posts from someone other than the candidate.

Stephen McNeil

Liberal Leader Stephen McNeil says candidates can overcome past online transgressions, but they need to be up front about them. (CBC)

If someone is to overcome past transgressions, he said, parties need to hear about it from the candidates themselves and not reporters or other sources.

"I don't think anyone believes someone should be punished for their entire life for something that they've done in the past," he said.

"But I do think the important part is it's an issue of making sure that if there is something, that you've actually communicated it to the party."

Tories, NDP affected, too

The Liberals aren't the only party in this election — or others, for that matter — to be affected by controversial social media posts.

On Monday the NDP's candidate in Dartmouth East, Bill McEwan, resigned from that race when a blog he used to write was brought to light. On Tuesday it was the Tories' turn: they dropped Dartmouth South candidate Jad Crnogorac for tweets they deemed to be over the line.

McEwan and Crnogorac's names will remain on the ballot, however, because the nomination period has already closed.

The 2015 federal election also saw all major parties losing candidates over past social media posts. Ala Buzreba, a 21-year-old Liberal candidate, stepped down from running in the Calgary Nose Hill riding after apologizing for offensive tweets she posted as a teenager. 

Several Tory candidates running in Quebec were criticized for controversial comments they posted online, and a federal NDP candidate in Nova Scotia, Morgan Wheeldon, was forced to resign after suggesting in a 2014 Facebook post that Israel was engaged in "ethnic cleansing."

Public is public

Mike Smit, a computer scientist at Dalhousie University, said it's not difficult to find information people have posted online, even if they've tried to hide or delete it. It becomes even easier, he said, if social media accounts aren't protected.

"If you've put it out there to be public, it's public," he said.

Jamie Baillie

Tory Leader Jamie Baillie says all parties are doing their best to vet candidates, but sometimes things are missed. (CBC)

All three major party leaders said on Tuesday that their candidates and potential candidates are subject to a vetting process, which includes examining social media use and accounts.

Although Tory Leader Jamie Baillie said parties expect candidates to be honest and up front about anything that could become an issue, he acknowledged it can be difficult to keep track of it all.

Still, in the case of Crnogorac, her offending tweets weren't difficult to find and not that old. Baillie conceded the party didn't do a good enough job in that case.

"We're doing our best to vet them and obviously we missed some pretty offensive posts that crossed an important line with me and we'll be looking at how we can do a better job of that vetting in the future."

Gary Burrill

NDP Leader Gary Burrill says finding the balance between what is a foolish mistake and what disqualifies someone from being a candidate can be a fine balance. (CBC)

NDP Leader Gary Burrill, who called McEwan's comments "entirely unacceptable," said even with the best efforts the vetting process can miss things.

Determining what is a foolish comment or a mistake from the past and what is something that disqualifies someone from running is a fine balance that requires "a lot of care and wisdom," he said.

As would-be politicians fall like dominos due to past social media posts, a Cape Breton University political scientist believes a process will evolve where potential candidates pre-emptively disclose past activity in an effort to minimize damage.

"We will see more examples, I predict, of candidates … before the heat of the campaign coming clean and saying, 'As I mine my past, as I look at some of the comments I made unreflectively, there are incidents and comments for which I now apologize and I want to assure the public that these do not reflect who I am,'" said Tom Urbaniak.

"I think we will see more pre-emptive confessions, if you will, going forward."​

Being defined by the past

In the absence of disclosing potentially problematic posts ahead of time, Urbaniak said candidates risk having those posts define them if they do come to light.

It's a particular issue for candidates without a strong previous public profile, he said, such as the three in this election, and a reason why someone such as Matt Whitman is able to recover publicly and remain in the race — he had a past record of public service to point to and it wasn't the first time the public at large was hearing about him.

Regardless, Urbaniak said the message from this election and others to anyone thinking about running is simple and not surprising.

"Be reflective, think before you press send, think about what your values are and make sure that what you're putting out there is consistent with what your values are."