Who is at fault if there are parked cars on both sides blocking your visibility and you get rear ended while backing out very slowly?

Unfortunately this is a sad situation.Just like when you have a stop sign at an intersection and the street you are turning into doesn't have a stop sign,the drivers without the stop sign have the right of way so they trust that you will not be entering the street until it's clear.

Obviously if they are driving recklessly and too fast they cause the accident but from the eyes of the police,they put you at fault,when you back up you have to check for pedestrians and any car movement.

make sure the cars blocking your visibility had not been parked illegally,that can be a decisive factor to avoid any claims just in case you go to court.