They are outraged by the crime, but also something else.
The number one comment liked by hundreds on the page was this one: "Millions spent on light rail and bought cameras at the dollar store?"
The quality of the video and pictures of the suspects is poor, but Silent Witness says it was important to get out there.
It was March 31st, just before midnight when three people approached a 42-year-old man. One man attacked him, punching him until he tumbled onto the tracks.
The three stole his bike and backpack.
It happened on the platform near Central and McDowell. Regular riders say on the light rail you have to be careful.
Saressa Irving refuses to ride the light rail at night alone.
"Not by myself, not if my mans not with me, I won't get on it, not by myself, it's kind of scary riding at night time," said Saressa Irving.
It's not great if it is producing suspect pictures like this, but better cameras are coming, says Valley Metro.
All 112 platform cameras are due to be upgraded, but a fiber upgrade needed to be done first says a Valley Metro spokesperson. Now that it's been done, they plan to upgrade the higher resolution cameras.
Silent Witness says the low-quality pictures may be enough.
"Seeing those three people together, the female, the two guys. that's going to be the key in this thing seeing how they move, someone has seen them before and is going to be able to call us up and say that's so and so, I know that person," said Sergeant Derek Elmore.
Anyone with information on who the suspects might be is asked to call Silent Witness at 480-witness.