can someone be a considered authority without being an expert.

edit:

I am using authority from the example in wikipedia

"One example of the use of the appeal to authority in science dates to 1923,[20] when leading American zoologist Theophilus Painter declared, based on poor data and conflicting observations he had made,[21][22] that humans had 24 pairs of chromosomes. From the 1920s until 1956,[23] scientists propagated this "fact" based on Painter's authority"

Painter presumably was an expert. So not sure why you are saying why its ok if the person is an expert.

https://en.wikipedia.org/wiki/Argument_from_authority