I checked the tags for this particular question and saw that it's also a request for a phrase and not just a word.
So, I suggest the words "a person with/ of integrity."
Of course "professional integrity" means a lot of things to different people. But here's a definition I find similar to how I see it:
The quality of behaving according to the rules and standards of your job or profession.
Here are a couple other ideas I got from a source about professional ethics:
An old labor rallying cry says, ``A full day's work for a full day's
pay." Every job has its pleasant and unpleasant aspects. But in
accepting a job, we agree to perform all of its duties, not just the
pleasant ones. (emphasis mine)
The physician's motto is, ``First, do no harm." This means that we
must assure that any product or idea that we deliver is as correct as
we can make it and has no unannounced defects... Our computer program
may be used as a module in a drug delivery system in a hospital or in
a guidance system in a passenger aircraft. We must be sure that if our
work is used as we say it can be, that it will perform as
intended. (emphasis mine)