The second biggest police union has publically accused the government of disobeying the law when ordering the desalojo of Sol. They have also explicitly offered their solidarity to the indignados of the 15M movement. In a document, of which I present a copy, the union explains that the delegate of the government gave three clear instructions to the police when ordering the eviction of Sol and Paseo del Prado:
http://spanishrevolution11.wordpress.com/2011/08/04/police-union-sides-with-indignados-and-accuses-the-government/
