The leader of an anti-monarchy group who was arrested at King Charles' coronation wants an apology from the monarch

• Insider spoke to Graham Smith, leader of anti-monarchy group Republic, at a protest in Scotland.
• At the king's coronation in May, Smith was arrested on suspicion of breaching the peace.

Graham Smith is determined.

The anti-monarchist is in the middle of a protest at King Charles' coronation celebrations in Edinburgh, Scotland, when we meet on Wednesday. Charles' official coronation was held in London in May, but the king was presented with the Honours of Scotland — the Scottish crown jewels — in a ceremony at St Giles' Cathedral on July 5.

At the protest outside the cathedral, I watch as Smith, wearing a bright-yellow T-shirt with the words "Not My King" printed on it, chants the same slogan from a megaphone with his fellow protesters to hundreds of onlookers.

I'm not the only member of the press in attendance. Amid the sea of people, I spot multiple reporters and camera crews interviewing Smith's colleagues. There is also a counterprotest among the crowd, a small group of royalists holding signs that read: "Charles King of Scots."

Smith is the founder and CEO of Republic, a UK anti-monarchy group. The organization gained a new level of recognition after the organization said on Twitter that six of its members, including Smith, were arrested at Charles' coronation in London on May 6.

In an interview with the UK's Channel 4, Smith said he and other protesters were arrested on suspicion of "conspiracy to breach the peace" and were detained for at least 16 hours, according to a video obtained by The Independent.

In the same video, Smith told Channel 4 that Republic had conversations with the Metropolitan Police about its plans for a "peaceful protest" for four months before the coronation and that police initially had "no concerns."

According to a Sky News report from May 9, police arrested 64 people on Charles' coronation day.

As Insider previously reported, the Metropolitan Police said on Twitter that they "made a number of arrests" on the day, and were holding the individuals in question "on suspicion of breaching the peace." Four others were detained "on suspicion of conspiracy to cause public nuisance," and three were being held "on suspicion of possessing articles to cause criminal damage," the authorities added on Twitter.

The police seized items from Republic members that they believed could be used as lock-on devices, Sky News reported at the time.

Days later, on May 9, a spokesperson for the Metropolitan Police released a statement expressing "regret" over the arrests, as an investigation was unable to prove that the protesters had intent to disrupt the event, Sky News reported. The statement added that the protesters were released with their bail canceled and that "no further action will be taken."

At Wednesday's event in Edinburgh, I asked Smith whether he received an apology from the royal family or Buckingham Palace after the incident.

"No, they have said nothing at all," Smith, author of "Abolish the Monarchy," said. "Probably at some point I'll write to the king and ask for some comment. We haven't done that yet, we're busy suing the police at the moment."

Smith said he is suing the Metropolitan Police over its response to the protests at Charles' coronation, adding that it's a "slow process" and that his lawyers are in the process of writing legal letters to the police.

"The police have only said they regret it, they haven't apologized, but I think they will at some point," he said.

"I've always been told that the point of the monarchy is to defend our liberties and democracy, and yet the king doesn't care when people get arrested," Smith added.

On the contrary, Smith said he has had a good experience with the police in Scotland. Republic members have attended multiple events during Royal Week, an annual celebration of Scottish culture marked by visits across the country by the royal family.

Smith said Scotland has "a different attitude" to anti-monarchy protesters and that the police have been "really good so far."

"They've let us get on with it," he added.

Buckingham Palace declined to comment when contacted by Insider. London's Metropolitan Police did not immediately respond to Insider's request for comment.