As of 2016, the only U.S. President to have earned a Ph.D. was Woodrow Wilson.
The professional way is to say that you have earned your Juris Doctorate degree. It is not wrong to say that you earned your JD degree.
Both Cissy Houston and Whitney Houston have an doctorate.
Woodrow Wilson was the only president that earned a PhD degree. Several were awarded honorary degrees. Obama holds a JD ( Doctor of Jurisprudence) which is the first law degree at many law schools.
Yes, having a doctorate degree typically means that you have earned the title of "doctor," but it depends on the context and field of study.
There are no known Presidents that had and/or have a doctorate in psychology if you mean American Presidents. Also outside the USA there are no Presidents who have a degree nor a doctorate in psychology.
doctorate degree
Woodrow was the only US president with an earned doctorate.
President Woodrow Wilson was the only president to have earned a PHD.
Having a doctorate degree does not necessarily mean that you are a medical doctor. The title "doctor" is commonly used for individuals who have earned a doctorate in a specific field, such as a PhD in a scientific or academic discipline.
The former is the usual form: I have a doctorate.
Woodrow Wilson was the professor with the earned doctorate .
Woodrow Wilson was the only U.S. President who had a doctorate.