MIAMI (CBSMiami/CNN) – Manuel Oliver, father of Parkland school shooting victim Joaquin Oliver, attended President Joe Biden’s speech on gun violence Monday afternoon, just two months after climbing a construction tower near the White House calling for President Biden to pass gun legislation.

Oliver was one of Biden’s invited guests in the White House Rose Garden as the president, Vice President Kamala Harris and Deputy Attorney General Lisa Monaco delivered remarks on actions the administration hopes will curb gun violence.

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“Today is a special day,” he told CBS4. “I have been to D.C. many times, but the fact that I am invited this time to the White House is evolution.”

In a tweet posted Monday, Oliver said he was attending the event in the shoes his son Joaquin was going to wear to prom in 2018.

“I’m walking in Joaquin’s shoes on my way to the White House to hear the president of the United States,” Oliver said in the interview. “Emotionally, there’s a lot going on – positive things going on – and I think there are no other shoes that would fit me better today.”

Oliver was detained by police in February after staging a protest near the White House on the four-year anniversary of the Parkland shooting. He climbed a construction crane and hung a banner with a picture of his son, one of the 17 people killed at Marjory Stoneman Douglas High School in 2018. The banner offered a critical message to Biden that “45k people died from gun violence on your watch.”

On the ground, a poster was on display that read, “Peaceful action in progress. It’s just my dad helping me make a statement. Sorry for the inconvenience.”

“I don’t want to hear promises,” Oliver said. “This is not a campaign. You are the president already. We voted for you. This is your administration. We want actions. We want things that could be effective today.”

At Monday’s speech, Biden took aim at so-called “ghost guns” – unregulated, untraceable weapons made from kits – will address a critical gap in the government’s ability to track them by requiring background checks before purchase and serial numbers on some of the components.

“I think he’d be thrilled to know that we’re doing something. But until we get it under control, I don’t think he’s resting so much at peace,” said Linda Schulman, mother of Scott J. Beigel, a teacher killed in the Parkland Shooting. “Here I am in April, sitting in the Rose Garden, trying to hold back tears because I could not believe what I was hearing. He came through with his ghost gun regulations.  It means the world,” Schulman said.

Though ghost guns make up a relatively small share of the guns recovered by law enforcement, they have been seen with increasing frequency in recent years.

Biden brought one of the kits to the Rose Garden on Monday, declaring the new rules “basic common sense” before holding aloft one of the weapons made from the gear.

“If you buy a couch you have to assemble, it’s still a couch. If you order a package like this one over here that includes that parts that you need and directs the assembly of a functioning firearm, you bought a gun,” he declared, striding over to the kit and demonstrating the ease of constructing the weapon.

“It doesn’t take very long,” he said. “Anyone can order it in the mail.”

Oliver said he is grateful to be heard.

“The fact that they’re listening to us is important,” he said. “Because, you know what, this is a journey that will never end for us. This is a fight that I am never going to win. It started by me losing the fight. Nothing is going to bring back my son, but there’s a lot that I can do in between.”

One of the things he said he would like to see is a national director of gun violence prevention.

“We want someone to address the issue directly,” he explained, “Someone who has nothing else to do but that. And he has a team working in that direction.”

Biden named Steve Dettelbach, a former US attorney from Ohio, as his nominee to lead the Bureau of Alcohol, Tobacco, Firearms and Explosives. The President’s previous nominee was forced to withdraw amid opposition in the Senate.

“This mission of this agency isn’t controversial – it’s public safety,” Biden said.

The moves came as gun violence and crime have ticked up in the United States, putting pressure on the White House to take action. A rash of shootings over the weekend underscored the emergency: Four people, including two teens, were shot shortly after a Major League Baseball game in Washington, DC, on Saturday night, police said. In Illinois, six people were found injured after a shooting occurred in a residential neighborhood.

Police are also investigating a shooting at a birthday party in Indianapolis where six people were shot and one person was killed. And two people were also killed and 10 hospitalized after a “targeted attack” at a Cedar Rapids nightclub, police say.

Routine deadly gun violence is a uniquely American problem. The US Centers for Disease Control and Prevention deemed gun violence a “serious public health threat” last year. Biden has made modest progress on gun control, but major steps like banning assault weapons or closing background check loopholes would require congressional action.

“None of this absolves Congress … for the responsibility to act,” Biden said.

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Gun violence traditionally spikes in the summer months, lending further urgency to Monday’s actions.

The new rule issued by the Justice Department seeks to rein in a type of weapon that has been seen more and more at crime scenes across the country. Ghost gun kits can be purchased online, and a weapon can be self-manufactured in as little as 30 minutes. Because regulators cannot trace them, ghost guns are appealing to criminals and those with criminal histories, according to officials.

The new rules require anyone purchasing a kit to undergo a background check, as is required for other types of firearm purchases. It also requires those selling the kits to mark components with a serial number, so the eventual weapon produced can be traced. And it mandates firearm dealers add a serial number to already built ghost guns they come across in their businesses.

“All of a sudden, it’s no longer a ghost,” Biden said of the new rules. “It has a return address. And it’s going to help save lives, reduce crime and get more criminals off the streets.”

“Ghost guns look like a gun, they shoot like a gun, and they kill like a gun, but up until now they haven’t been regulated like a gun,” John Feinblatt, president of Everytown for Gun Safety, said in a statement celebrating the Biden administration for “doubling down on its commitment to gun safety.”

Mia Tretta, who was shot and wounded with a ghost gun in a school shooting in California in 2019, similarly praised the administration for taking “a critical step” with the new regulation. Tretta introduced the President in the Rose Garden on Monday.

“If you can put together an IKEA dresser, you can build a ghost gun,” she said in a statement. “Unfortunately, it is that easy to get a weapon that has not only changed my life but has done the same thing to thousands of others. Finalizing this rule is a critical step to making sure no one else has to go through what my family has had to go through.”

The Justice Department previously launched a national ghost gun enforcement initiative, which will “train a national cadre of prosecutors and disseminate investigation and prosecution tools to help bring cases against those who use ghost guns to commit crimes,” according to the White House.

Biden said Monday that those who commit a crime using a ghost gun should “expect federal prosecution.”

“This rule is an important step. It is going to make a difference, I promise you,” Biden said.

Ghost guns have been used in multiple recent shootings, including at a Maryland high school in January. The exact number in circulation is unknowable, given the inability of regulators to track them.

“We don’t have many good days often. I think this is a small victory,” said Oliver.

Between 2016 and 2021, the ATF received 45,000 reports of privately made firearms recovered by law enforcement, including 692 from homicides or attempted homicides. The agency was able to trace only 1% of them, officials said, because the firearms lack serial numbers.

Multiple states have moved to restrict their sale as ghost guns become more common at crime scenes.

Last week, Maryland joined Washington, DC, and 10 other states – California, Connecticut, Delaware, Hawaii, Nevada, New Jersey, New York, Rhode Island, Virginia and Washington – in banning or restricting the purchase or use of ghost guns, which are often bought online and assembled at home.

Senate Majority Leader Chuck Schumer again decried the use of ghost guns during a press conference Sunday, calling for a crackdown on the rise of the privately made firearms and speaking about a deadly shooting in the Bronx Friday.

The New York Democrat blamed Republicans for holding up gun reform legislation, while pressing Biden’s administration to go further. “Today I am calling on the administration to go all after ghost guns, by putting out regulations that will stop them. The federal government has the ability through regulation to stop these ghost guns,” he said.

Still, Biden’s planned firearm regulation drew backlash from gun rights advocates even before being officially announced.

Aidan Johnston, the director of federal affairs for Gun Owners of America, said in a statement Sunday, “Biden’s proposal to create a comprehensive national gun registry and end the online sale of gun parts without the passage of a new law exemplifies his disregard for the Second Amendment.”

In September, Biden withdrew his nomination of David Chipman to lead the ATF after facing opposition from Republicans and certain moderate Democrats.

Chipman, a former career official at ATF, came under scrutiny from gun rights supporters and the National Rifle Association for his work as a senior adviser to Everytown for Gun Safety and Giffords — the organization started by former Rep. Gabrielle Giffords, who was shot at an event in her Arizona district in 2011.

Dettelbach ran unsuccessfully for Ohio attorney general in 2018 after serving as US attorney in the state.

“We will be working hard to ensure that Steve Dettelbach receives the fair hearing and confirmation that he deserves. He should be a noncontroversial candidate because he has a long record of working in law enforcement and for the public safety of the people of Ohio and the American people,” one of the officials said.

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CBSMiami.com Team