I am often asked if it is required for therapists to have been in therapy. And most people are surprised to learn that except in the case of analytic training and a few other programs, it is not a requirement. In fact Casey Truffo cites a survey suggesting that 20-25% of therapists report they have never themselves been in therapy. And I have heard suggestions that therapy should be a requirement for licensure.
I believe it is important for a therapist to have been in therapy and probably to return to therapy periodically throughout her career. Why? Because I need to be able to sort out my own personal issues from those of my patient and that is very difficult without having done work in therapy. Just as I cannot see my own back without a mirror, so too I cannot see my shadow and blind spots without benefit of the mirror of therapy. It is not a function of how happy one's childhood was because none of us come to adulthood without issues, without shadow. It is matter of the major importance of self-education, the kind that can only come, I believe, through the process of engaging in self-exploration with a good therapist.
Now I actually think the 20-25% figure for therapists who have not been in therapy to be a bit low. Because I know of many more people drawn to the field as problem solvers than there used to be. It seems to me that those who work in a solution-based model or problem solving model, where the focus is on teaching the client techniques for changing behavior or resolving problems are less likely to see any need themselves for therapy -- because, in my mind, what they are doing is not therapy but counseling.
That a therapist has been in therapy is of course no guarantee of skill or excellence, but at the very least such therapists understand what it is like to sit in the patient's chair and talk. That alone is important.
Perhaps paradoxically I would not make experience in therapy a requirement for practice. I don't that compulsory therapy is likely to make much difference for those who would not choose it for themselves. Robert Langs has an interesting concept called lie therapy, in which therapist and patient collude unconsciously to avoid confronting material and to not engage fully in the therapeutic process. My guess is that if therapists are compelled to be in therapy, many will seek and engage in lie therapy in order to satisfy the requirement without threatening the status quo of their psyches.