The U.S. Department of Education and the National Science Foundation recognize numerous non-professional, research-oriented doctoral degrees (such as the Doctor of Liberal Studies) that require a dissertation or corresponding project as equivalent to the Doctor of Philosophy (Ph.D.) and does not discriminate between them.
The U.S. Department of Education and the National Science Foundation acknowledge that non-professional, research-focused doctoral degrees such as the Doctor of Liberal Studies are considered equivalent to the Doctor of Philosophy (Ph.D.) and do not discriminate against them.