Well, yes, it would be, and it looks like the guilty plea isn’t to burning a Koran as such — it’s essentially to threatening people in a note accompanying the burned Koran. The man (Adam David Smock) was charged with “participating in a conspiracy to oppress, threaten and intimidate worshippers at the Islamic Center of Springfield in the free exercise and enjoyment of their constitutional right to the free exercise of their religious beliefs.” The “oppress” doesn’t have much independent meaning in this context; rather, the charge is that he was threatening worshippers with violence — as the plea agreement says, “[t]he defendant … admits” that he acted “to threaten and intimidate worshippers.”
And there were indeed statements that could well be threats accompanying the burned Korans:
Smock also admitted that on April 10, 2011, he and the same two individuals partially burned two copies of the Qur’an, the Muslim holy book, and Smock left the burned Qur’ans directly in front of the main doors to the Islamic Center, approximately 30 feet away from the building, where a co-conspirator also left a computer-printed note that contained the image of a goat’s or ram’s head, and the following text:
A reasonable person might well see “Death to Islam,” in the context of “Muslims” “stain[ing] the earth,” coupled with the vandalism of the mosque, as a threat of death (or some violence) to Muslims as people and not just to Islam as an ideology. And recall that Smock in the plea agreement admitted that he had the intent to threaten.
So it’s not the burning of the Korans that was the crime: it was the threatening speech, which would have been criminal threats even if it had just accompanied the vandalism, with no burned Korans left on the scene. The prosecution seems sound, but the headline on the news release strikes me as misleading. Consider as an analogy, for instance, a release saying “Man pleads guilty to defacing U.S. Army recruiting office and burning the American flag,” where in fact the man pleaded guilty to trying to threaten violence against recruiters in a note accompanying the burned flag (and in the defacement of the recruiting office).