social media search and seizure?

Ever worry about what you’re posting on social media? The NYPD is using social media now, except they are using it to catch criminals. (How about now?) NYPD’s Facial Recognition Unit searches Facebook and Instragram for photos of suspects in order to track them down and uses features like shape of the eye, nose and cheekbones to match images, which by the way is revolutionizing investigations.(Worried now?)  Via