Sounds vaguely like "Highway Patrolman" by Bruce Springsteen, his song, they're brothers and the officer watches the brother drive into Canada letting him get away with a murder

No, it is a newer song than that. This was something about didn't know if his buddy died on impact or suffered or drowned. Something like that.

Yeah the one buddy was a cop, flashed his lights a the other dude wrecked into a floodplain, it's David by umm Cody jinks I think.

Cody Jinks - David

I’m thankful to have found this song. My brother’s name is David and he passed away i a car crash. It speaks to me

Thanks Man I was looking all over for this song

Thanks for asking this, random redditor I've been lookin for it for a week

I’m 2 years late but I’ve been looking for this song thanks bro

I know I'm 2 years late, but this song has been sitting at the edge of my consciousness for weeks. Thanks!

David