Given the limited details given about the placement of the deer (over a hill, on a sharp curve, etc.) you might wish to "rethink" your comments placing the majority of the blame on the driver.
Placing the decoy around a corner does make it more difficult to be spotted, especially at night, and would make doing so even more reckless of an act by those placing it there.
However, it is still the driver's responsibility to slow down for the corner and to be able to stop in time if something is on the road.
What if a car had broken down on the road? What if a bail of straw had fallen off of a truck? What if there simply happened to be a kid standing on the road that froze at the sight of an oncoming car instead of running off to the side? What if it was just a large dog standing in the road (not that uncommon in rural areas).
A car is an incredibly dangerous piece of equipment if operated without the proper caution. Having the item on the road be behind a corner or a hill doesn't lessen the responsibility of the driver to be in control.
It would add to the level of stupidity of the kids putting the decoy on the road, because corners do reduce visibility and while even a careless driver should see something in the road on a strait section of road, they need to pay more attention or go slower to deal with surprises in a corner.
However, if a car breaks down in a corner, and another car comes flying around the corner and hits it. It's not the driver of the broken down vehicle that will get cited for causing the accident. Drivers are responsible to be able to stop their cars in time to not hit objects on the road.