MIAMI (CBSMiami) — Sunday will mark three years since 17 people were killed and another 17 injured in the Marjory Stoneman Douglas Senior High School massacre.

Thursday, the parents of murdered student Joaquin Oliver unveiled a unique campaign in their fight for gun reform.

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They’ve created “shame cards.”

They are post cards highlighting mass shootings from across the county.

They will be sent to lawmakers urging them to support “common sense” gun laws.

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“How can a regular civilian with no experience have access to an assault weapon, I don’t get it,” said Manuel Oliver.  “Large capacity magazines that’s not about your safety and making sure your freedom is okay, that’s just to kill a big amount of people in a short amount of time,” he said.

“Greetings from Parkland, Florida” says the colorfully illustrated postcard.  But upon closer, within the outline of the word Parkland is some gruesome imagery from the horrific massacre and the self-confessed shooter handcuffed in court.

There are more than 50 postcards meant for members of Congress.

The Oliver’s say their son Joaquin is not a victim, he’s an activist whose goal is to save lives.

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Those shame cards are also available in digital form at shamecards.org.

CBSMiami.com Team