Stepdad has dementia. Mom's in nursing home now 23 days. Should stepdad be driving to and from nursing home 3.4 mi. away?

No one with dementia should be driving.

No, but will he give it up? No one with dementia should be sent in a taxi by themselves, either.

Does his county offer some sort of senior ride service? He may not be able to go every day. That's just reality.

Maybe he is a candidate for IL or AL in the same facility?

No, he should not be endangering the other drivers on the road. Your local government may have a shuttle service for seniors. If not, or in addition, call the nearest taxi company and see if you can hire a driver to take him back and forth every day at specific times and ensure that he gets into the facility and then back into his home. (I know of a taxi company that did this for a senior to go to and from church every week.)

NO!
He should not be driving anywhere!
Help him to find a ride. Offer to drive him, find a friend or volunteer to drive him, or help him use Lyft or Uber.

Disable his vehicle so he can not use it. It is not safe for anyone with dementia to be driving!

Om my goodness, 100% no absolutely not

I would not recommend him driving to and from the hospital. Maybe you can find alternative transportation services.

Good Lord, NO!

My mother with mild dementia would not stop driving, even after her license was taken away. It wasn't long after that she drove right into the back of a parked pickup truck. Her car was totaled, and she went to the hospital with broken ribs, and from there to a nursing home for the rest of her life. Every time I think of this I get chills thinking how fortunate it was that she didn't injure or kill someone.

In retrospect, I should have disabled or removed the car and not believed what she was telling me about not driving.

Absolutely not. Arrange a ride for him.

Do you think it's okay for anyone to be driving when they have dementia?

Hint, hint. It's not.