Just like your lazy kid who can't be bothered to assemble a 1032-brick LEGO set his grandmother gave him for Christmas, our dedicated "white supremacist domestic terrorist insurrectionist" apparently never got around to actually building that Capitol set.
Here is the relevant passage from the FBI's statement:
In the original detention memoranda…
You know, the one used to justify placing the man in custody, so nothing requiring enormous amounts of care or anything.
...the undersigned stated that law enforcement found a 'fully constructed U.S. Capitol Lego set.'
I do recall seeing that, I'm not sure exactly where, though. It could have been the lead story on every major news site for a day.
Yeah, now that I think about it, that was it.
Please note that after a review of the photographs from the search, there appears to have been a miscommunication…
It's like the telephone game that kids play. You know the one, where the agents on the scene tell the investigators one thing, the investigators tell the DA something else, and then by the time the DA tells the judge the original story is all hilariously mixed up!
And someone goes to jail.
Good for hours of family fun, not to mention arraignments.
…that statement appears to be inaccurate. The Lego set was in a box and not fully constructed at the time of the search.
I can understand why it required a careful forensic examination of the photographic evidence to uncover the error.
I don't know about you, but that closed box sitting forgotten in a storage container could easily be confused with a fully constructed LEGO set. Besides, the fact that it is partly covered by a discarded hat of some kind demonstrates mens rea, or "guilty mind," a legal concept that,
...allows the criminal justice system to differentiate between someone who did not mean to commit a crime and someone who they really want to prosecute.
I may have paraphrased that a bit.
It is also well understood that LEGO sets are routinely used by terrorists. In fact, I have it on good authority that the 9/11 hijackers made use of this LEGO set to plan their attack.
Some people might argue that law enforcement purposefully mischaracterized what they had found in order to establish a narrative early that they knew would endure long past any corrections later buried in news reports but don't you worry about that. Those people are already under surveillance for having suspicious piles of scrap wood in their sheds.