Fixing his own vehicle... for sure...
If you think there needs to be an escape hatch to fix injustices then you have a bigger problem.
That said, I have never seen the current administration do that.
If you assume, hypothetically, that the justice system is operating as it should, a pardon means giving one person the right to ignore the laws of the country for a select few acquaintances.
If one has to tolerate this blatant avenue for favoritism, I’d rather see the Supreme Court or judges themselves invested with this power, rather than the president.
I guess I am biased by believing in the separation of the executive and judiciary powers.
Another example where pardons might be useful is when laws are changed after sentencing. If the new law does not provide for retroactive adjustments, a president or governor can grant clemency in order to correct disparities in sentencing outcomes.
I see a lot of ancient big trucks on the road today that are completely legal in Texas but would probably get you sent straight to jail in Europe. The owners of these vehicles are oftentimes also diesel mechanics to some degree and can make their machine run much longer than they can.
The problem with all of this is that there is this entire niche of the market that you simply cannot penetrate with policy. I think some of these old trucks should be taken off the road, but I also sympathize with the owner/operators of these vehicles. I don't think many people drive a big dump truck around for fun (even in Texas). That's mostly a phenomenon on the consumer side. Rolling coal out of your Ram 3500 isn't something that really bothers me. The optics are horrible, but the actual impact is not. The thing that concerns me is the fleet of old Kenworth trucks from 1988 that the local construction company uses all day every day. Straight pipes and a constant rumble the USGS could monitor tend to drown out the broader concerns regarding emissions, but those also pop into your mind if you happen to be riding behind one.
I think a lot of the defeat device stuff is blown out of proportion for political reasons. Something approximating this has been going on since the 70s. Anything pertaining to consumer vehicles makes me roll my eyes. The studies they ran around VW are absolutely hyperbolic (hundreds of billions in damages, 100k+ dead eventually). Compare the marginal impact of slightly cheating emissions standards in a family sedan with one supermax cargo ship or a data center parking lot full of gas turbines and you'll probably find you are wasting your energy on the car thing. The deception is what makes most people angry. Not the actual impact.
I don't really understand how the rest of your comment provides evidence for this claim. Not wanting to address it with policy, sure, I can see you seem to feel that way, but it's not clear why you're convinced it can't be addressed.
From your link:
> the practice can increase nitrogen oxide emissions as much as 310 times, non-methane hydrocarbons 1,400 times, and carbon monoxide 120 times
Note that at least one of the men, Jonathan Achtemeier, was caught doing much more than "rolling coal" himself. He led a nationwide conspiracy to "roll coal", charging money to help hundreds of people do it although he knew it was a crime. Career criminals like Mr. Achtemeier rarely stop when they get caught the first time.
Any time a President can use their pardon power to free any actually innocent person from a genuinely unjust act, they should do so.
Problem is, we've got Presidents who'd rather abuse it arbitrarily in unjust fraudulent ways. Thus, "pardon power" probably just shouldn't exist at all I suppose, or it should have some sort of "guardrails" / oversight somehow attached at the very least least...
If I may suggest anything, perhaps replacing the president should be made easier, either by making the people be able to recall the president, or by recalling the congressmen, and the congressmen then follow through with impeachment. Or both.
You may indeed suggest it. Now, how do we make it reality so that "We The People" can get some of our power back in this supposedly "Free" nation?
Diesel cars used to be really reliable. And then, in a moment, they got that ecology thing. They leaped from 500k+ kilometers until the first major expenses to just 100k+. From a consumer point of view, you were just buying the next version of the same diesel car. But in reality you get nothing even close. If that's not a deception, then I don't know what a deception is.
Many modern diesel cars require very expensive replacement parts after just 100k kilometers. I mean really expensive. I had Fiat Tipo and the particle filter would cost me €5000+. Which is more or less half the car market price. After trying "cheaper" approaches that mounted to the same €5k over the 1.5 years, without resolving the problem, I decided to sell the car.
On the other hand, this is just an ecology thing. Your car can perfectly live without it. You can turn it off for a fraction of that cost. After a year of trying different approaches, my mechanic even offered to do it for free. The temptation is very strong. You didn't plan financially for this kind of repair costs when you were buying a diesel car. You need your car to keep going for another 2-3 years at the very least to make the purchase feasible.
Of course, you can call it a customer mistake. After all, the manufacturer didn't provide a warranty beyond 100k kilometers. But nobody tells you that the car takes €5000+ in repairs per 100k kilometers.
I'm all hands for the ecology. Don't get me wrong. I didn't accept the offer to remove the insides of the particle filter. However, if I didn't have the money to buy a new car, I would certainly do that. With my conscience being clear, because I'm 100% sure that the manufacturer is the one who is responsible for this. And the governments who allowed this manufacturer to behave like that. I'm OK with paying the "ecology tax", but it should be clearly stated in the papers, and not shadily emerge after 100k kilometers.