I can't speak for elsewhere but here in Canada there have been a small number of cases of stroke and death induced by Chiro procedures.
The manipulation which they do that may be helpful is also performed by physiotherapists. It has been many years since I personally went to a chiropractor but I have relatives that have been within the last few years. I have received manipulation from both.
The difference is that the physio gives warnings about the risks of such manipulations. Chiros did not to my relatives in the fairly recent past. The other difference is the degree of care and gentleness exhibited by physios.
The physical therapy profession here is guided (to a high degree) by evidence for effectiveness. The chiropractors are not.
As of a decade ago physios received more training in the specific treatments and a great deal more. The Chiropractic college here spent rather more time on running the business.