I recall reports of several of the Little Havana crowd (including the great uncle, he who had been in the US for ~15 years and still spoke no English) claiming or suggesting that they had weapons in the house or nearby. I think the great uncle's bravado, playing to the crowd, led Justice to believe that a quick & powerful operation was in order.
The Little Havana Gonzalezes were in direct violation of a lawful order from the DOJ. No US Court ever decided that it was appropriate for the Court to intevene in an area of obvious Executive purview.
The report that there was a gun in the house ( legal in this country, at that time ) came to Reno through a major US intelligence resource named Fidel Castro.