The hashtag created to promote Ontario's Police Week was taken over last week by critics questioning police accountability and sharing stories about being stopped by officers.

Since 1970, police forces across the province have been marking the week with barbecues, community meet-and-greets and recruitment drives.

Last year, they included social media in the PR campaign using the hashtag #PoliceWeekOnt.

TNX 2 every1 who showed support 4 our <a href="https://twitter.com/hashtag/police?src=hash">#police</a> officers. UR never in the news but we know UR out there <a href="https://twitter.com/hashtag/PoliceWeekONT?src=hash">#PoliceWeekONT</a> <a href="http://t.co/V1JqaxvGHD">pic.twitter.com/V1JqaxvGHD</a> —@OACPOfficial

But this year if you clicked on the hashtag, you would likely have seen a series of pointed questions about police conduct and accountability.

Jared Walker, who works in communications in Toronto, was among those who took over the hashtag, posting stories about how police in Ontario interact with their communities.

"Myself and a group of other folks decided to talk about one of the important and hot-button issues that has been gripping the city, which is the issue of carding," said Walker.

Carding is the practice of officers stopping, questioning and collecting information on people without arresting them. The Toronto Police Services Board approved a revised set of guidelines for carding in April.

Walker calls carding "illegal, unconstitutional and alienating."

He said he was stopped and questioned by police when he was 14, cutting through a park in Forest Hill, to get to school at the private Upper Canada College. He said the police didn't believe he went there.

How do black youth in Toronto <a href="https://twitter.com/hashtag/DiscoverPolicing?src=hash">#DiscoverPolicing</a>? I was 14, cutting through a Forest Hill park on my way to high school... <a href="https://twitter.com/hashtag/PoliceWeekONT?src=hash">#PoliceWeekONT</a> /1 —@JAWalker

The school was <a href="https://twitter.com/UCC_Community">@UCC_Community</a>. I attended on full scholarship. I heard a siren sound once, a car w/ 2 officers pulled up. <a href="https://twitter.com/hashtag/PoliceWeekONT?src=hash">#PoliceWeekONT</a> /2 —@JAWalker

They asked me what I was up to on that street, if I was lost. I explained I was going to school. They asked where. <a href="https://twitter.com/hashtag/PoliceWeekONT?src=hash">#PoliceWeekONT</a> /3 —@JAWalker

I said UCC. They didn't believe me, asked why I wasn't wearing uniform. I said I kept it in my locker to put on at school. <a href="https://twitter.com/hashtag/PoliceWeekONT?src=hash">#PoliceWeekONT</a> /4 —@JAWalker

Still looking skeptical, they asked my name, where I lived, etc. I started frantically going through my bag for evidence <a href="https://twitter.com/hashtag/PoliceWeekONT?src=hash">#PoliceWeekONT</a> /5 —@JAWalker

I produced a planner & spare school tie which I held feebly as proof. My hands shook. 1 of them looked through my planner <a href="https://twitter.com/hashtag/PoliceWeekONT?src=hash">#PoliceWeekONT</a> /6 —@JAWalker

Satisfied, they got back in their car & drove away. I sat, shaking with the contents of my bag all over the sidewalk. <a href="https://twitter.com/hashtag/PoliceWeekONT?src=hash">#PoliceWeekONT</a> /7 —@JAWalker

I was late that morning & didn't want to say why. I couldn't think of another excuse & I'm pretty sure I got a detention. <a href="https://twitter.com/hashtag/PoliceWeekONT?src=hash">#PoliceWeekONT</a> /8 —@JAWalker

The Toronto Police Service defends carding as an essential police tool. Police chief Mark Saunders said ending carding would result in a "loss of intelligence" for police.

During the first day of the online protest, critics posted more than 1,500 tweets on the hashtag, but there was no reply from police on Twitter.

Toronto police spokeswoman Meaghan Gray told the Metro newspaper that she didn't think critics on Twitter "intended to engage in a mutually respectful and productive conversation."

"I think it speaks to what one thinks of service if you think that you can ask for dialogue and then refuse to dialogue because you don't like the tone of some of the questions being asked," said Walker.

"Dialogue is a two-way street. You say something, people say something back. You go somewhere," he said.

In the National Post, Joe Couto, director of government relations and communications for the Ontario Association of Chiefs of Police (OACP), said lack of an official response on Twitter was due to the "complex issues" raised that couldn't be properly addressed within "140-character limits."

Since then, the OACP has responded to the criticism and questions posted to Twitter, saying they will look at all the tweets, set up a meeting with community members and write a report.

The Police Week case highlights the fact that the creator of a hashtag really has no control over what people do with it. You can't "own" a hashtag like a website address.

Last month, the hashtag #dontHave1million went viral after a Vancouver woman started a Twitter conversation about the city's skyrocketing real estate prices.

But soon, a group of realtors and mortgage brokers started using the hashtag for their own promotional purposes, and registered a Twitter account and website address with similar names.

Not only have hashtag takeovers happened before, they've happened to police before.

Last year, police in New York urged people to post photos of friendly officers under the hashtag #myNYPD. Instead, it filled with images of police violence.

Police forces should have expected criticism via the Police Week hashtag, said Walker.

"They started the hashtag in order to dialogue with the community about policing," he said. "The success of … using this hashtag to talk about carding and police accountability is pretty clear. If you look at the tweets the police have been tweeting, which are not engaging with us at all, they have not been retweeted. They have not been favourited. They're not going anywhere."

Walker likened using a hashtag created by police to criticize police to a hip-hop artist sampling another musician's work and reworking it into something new.

"I'm actually reminded … of a Jay-Z lyric," he said. "He's talking to one of his rivals in [Takeover]. He says, 'Yes, I sampled your voice. You was using it wrong. You made it a hot line. I made it a hot song.'"