I should have had one when some woman cut me off in the center lane of the highway, in heavy traffic, then slammed on her brakes hard. My brakes were in need of replacement, and there were cars on either side, so all I could do is slam on mine and hope she didn't come to a complete stop ... which she did, so collision was unavoidable. I couldn't see ahead of her as I always drive small/cheap economy cars (My Chevy Sonic in this case), but when I asked what the trouble ahead of her was, her only response was, "I don't know".
There was a basketball-sized dent in the bottom of her bumper cover, in a matte plastic portion that looked like it would just pop out, as there was no paint. My front bumper cover cracked and the cheap plastic grill broke.
This was in the middle of January, in Wisconsin, so we were in the single digits Fahrenheit for temperature. She immediately said we should exchange information and just get on our ways, because she had a child in the back seat. The windows were tinted, so I couldn't tell for sure, but I didn't see anything that could be alive back there, but agreed.
I was obviously disturbed by what had just occurred, since this was the newest car I had ever owned, and had only owned it for a year. One of the few things she did say was, "Well, at least nobody was hurt." as if that was supposed to be comforting or something. That became a pretty ironic statement later.
I called the DMV the next day and they said that if the damage was below a certain threshold, I believe it was a few thousand, they assured me that the accident didn't need to be reported. I figured there was literally 0 actual damage to her vehicle, and I planned on just picking up a bumper cover at a pick-and-pull for a few hundred bucks and slapping it on there, so I figured that was a done deal.
A few weeks later the insurance company calls and says that she reported the accident, and asked whether or not there was a child in the back seat. I explained that I couldn't be sure, but I sure didn't see one. They said they would send an assessor, and that was the end of the conversation. Not once did my insurance company ask me my side of the story.
The assessor called a GM dealership and, of course, the dealership came up with some ludicrous number like $3,000. I only paid $4,000 for the freaking car. I eventually found out from him, in later phone calls, that the other driver, and supposed child, claimed to have injuries and was suing my insurance company. I asked him whether or not anybody was ever going to ask me what happened. He seemed stunned at this question, but continued on with the conversation.
Long story short, in the state of Wisconsin, regardless of the circumstances, the first driver to rear end another vehicle ... for literally any reason at all, is considered at fault. This was over a year ago. It was my first and only accident, in driving for the last 15 years. Monthly insurance costs still haven't gone back down to what they were.
I wish I had had a dash cam. That's for sure.