After following it for five or so miles and seeing it nearly swerve into a vehicle that was passing it on the right, we called it in.
Since it was traveling pretty much the same speed as we were and I did not feel safe passing a swerving vehicle on the right, we stayed behind it.
After we followed it for another nearly 30 miles, we called it in again.
We followed it for a total of around 100 miles and lost sight of it when it got dark. NO LE ever showed up.
What should we have done?
Solo, I saw it swerve toward 3-4 different vehicles as they were passing it. I did not consider passing it on the right (which is probably not legal) to be a safe option.
BTW, the vehicle had Colorao tags and we discussed options
High on MJ
Elderly
Medical condition
Sleepy
Occupied by electronics
There was something different about how this car acted than what I typically think of as a drunk or sleepy driver.
Seriously, you did the right thing. I have called 911 after coming upon 2 auto/pedestrian accidents (neither lived). If either or both of those would have been prevented by a stop/check by the police, it is well worth it.
Afternoon can be a time when drivers get sleepy, especially if they've been behind the wheel a few hours. You'll find drunks any hour of the day, as well, so speculating on the reason they're all over the road can be a crap shoot.
Watched a drunk wrap himself and his car up in about 100' of hurricane fencing one time. Had called the cops and was on the phone with them when he finally lost it off the right side. Fire Dept. had to come and cut all the chain link fencing away so he could even get out of this car..drunkeranhell.
Seen dozens fall asleep behind the wheel, most often in the wee hours of the morning just before sunrise. Also seen a few heart attacks, one was a big truck driver I was running across Texas with. He just said "Oh $hit" on the radio, and his truck slowly moved to the shoulder and stopped, with me right behind him. He was dead (as best I could tell) by the time I ran up there and opened his door, so I pulled him out to the ground and did CPR til the DPS and Fire guys arrived. Unfortunately it was of no help.
Spend enough time running back and forth across the country and you'll see it all.
Seriously, no more then what you say happened, you did the only thing you could. Rural police are strapped. Huge patrol areas and demands on few officers means priority sees some calls go unchecked in timely manners. My brother and I were pulled over one time due to his eradict driving. We were not under the influence. Just talking. So, he may every well have not been doing anything wrong other then riding in the left lane and not paying enough attention to the road. God Bless
Unfortunately, this can be true. There are many ways drivers get distracted and birdwatchers are not immune.