She is not displaying her cleavage in public for all to see. In a public place your argument would have merit. Regardless of what picture is taken, one cannot take pictures of people where they have a reasonable right to expect privacy.  Now maybe a private business would not put up a stink, but in a taxpayer paid institution, there are strict protections. 
A lot of people think they can't be photographed in public, but they can as long as the photo is not used without their permission for personal gain. I've taken pictures of people driving and texting and they are livid, claiming I have no right. But I do as long as I don't make money from the photo.