Police say they have enough evidence to prosecute 32 motorists involved in a 150-car pile-up on the New Sheppey Crossing Bridge in Kent.
But officers said rather than drag the alleged offenders through the courts, they will send them on driver alertness courses instead.
The huge crash during rush hour on September 5 last year is believed to have been the biggest accident in thick fog in living memory.
It continued for 10 minutes as cars and lorries smashed into each other in visibility of just 25 yards.
Eight people suffered serious injuries and 200 others were treated at the scene.
Inspector Martin Stevens, head of the serious collision investigation unit at Kent Police, said it was “quite simply a miracle” that no-one was killed.
Some motorists reportedly drove “like idiots” before the crash, which closed the bridge in both directions for more than nine hours.
Officers are sending letters to 32 drivers involved in the crash, offering them the chance to attend a one-day driving awareness course rather than go to court.
Those who decline will automatically be summonsed to court, Kent Police said.
Insp Stevens said: “This has been a thorough investigation of what was the biggest collision in the county and certainly the largest our team has had to deal with.
“Clearly the thick fog that descended on the bridge that day made driving conditions incredibly challenging and was a contributory factor in the resulting collision which stretched from the approach right across the bridge.