Bray subsequently claimed the Master Sword was a “fidget” — something to keep his hands busy — that he had bought online. But police said that because it was a sharply pointed item, it could be used as a weapon, and “put others in fear of it being used against them.” The police said the Master Sword was inside a sheath and could be released with the press of a button.
So, it wasn’t that he was just carrying it.
They literally said it was inside of its sheath directly in the quote you posted…