This thread is rehashed every few months, but here are my thoughts:
Psychologists: Absolutely not. Psychologists do extensive training and have an amazing skill set. I have learned A LOT from the experienced psychologists in our department, but they are not physicians and should not be prescribing medications. Agreed with above about learning how to manage crisis situations during residency. Also, since most of our drugs have noticeable side effects, anyone who prescribes them should have them at the forefront of their mind and how to quickly evaluate and address them. For example, in clinic I had a patient on a MAOI complaining of stiffness and diaphoresis, and though his vital signs are stable I knew automatically I would have to look at reflexes, bowel sounds, etc. (pt did not have serotonin syndrome btw, just a little anxious). This is pretty basic for any doctor because even in 2016 when physical exams are hardly valued, we still know the basics. However, this is not in line with psychologists' training. They can take all the psychopharm courses available, but the absence of clinical experience of being responsible for medically ill patients (learned during medicine months on intern year), prescribing rights should be limited to physicians
Midlevels: Useful for clerical work where you need someone to sign off or make basic dose adjustments. One of our attending only clinics is set up like this and works pretty well. The attending is responsible for the initial management and sees the patient every few months, but the NP does most of the grunt work. I would not trust an NP with starting clozapine, lithium, MAOI, TCAs etc
I think one of the great myths perpetuating our field is that psychopharmacology is "easy." Yes, treating a psychiatric patient involves much more than just treating symptoms with medication, but using medications correctly (especially more complicated meds with potentially significant side effect burdens) requires considerable training, thinking, and reading of the literature. For example, I regularly think about fundamental pharmacokinetic (half life, volume of distribution, clearance) and pharmacodynamic principles and how they might influence drug choice/response in a given patient. Academic psychologists may consider these issues in prescribing (but lack the clinical medicine experience to understand how loosely they sometimes apply), but I doubt an NP would even think about them beyond (oh check xxx level after 5 days because this is what I head someone else do) I also regularly read both the old and new literature to understand phenomena I didn't expect and various nuances to prescribing.
There are obviously plenty of lazy, board certified psychiatrists who make egregious mistakes: when I was covering the ED a few weeks ago I had to see an OSH transfer because an RN who was a licensed "psych evaluator" noted that the patient was "manic", "delusional," and had "flight of ideas" (none of which were accurate btw, he was delirious), but in looking at the history the patient was recently hospitalized for delirium 2/2 hyponatremia and a psychiatrist tapered of his Xanax 4mg TDD (probably had been on this for years) using 2x Klonopin equivalents in 4 days... so he was in benzo DTs. However, I think in the academic bubble things like this are magnified 10x and are mostly the exception rather than the rule (and happen plenty in most other specialties, btw). And I find fallacy in the claim that the existence of incompetent doctors justifies psychologists and midlevels to prescribe. Hopefully with higher quality medical students choosing psychiatry this becomes less of an issue...
