I tried to find the records of my great uncle Bernard Seidel who was on the force from about 1918 until 1943. I did not have much luck from any official source. However i also contacted the NYPD police museum and to my suprise they had a photo in his file and sent a copy of it to me. i also found osme articles in the NY Times on line archieves describing several arrests he was involved in. One final source might be old issues of Spring 3100, the police department official magazine. I have not found a centeral point where the old copies are stored but they might have articles or his retirement dates which they published monthly. If you can find the exact date of retirement you may be able to get that exact isseu on E bay. I took a chance a purchased a overview issued and to my good luck there was an article about antother retired detective that contained a photo of my great uncle next to a weapons cache they had uncovered in about 1923.
Good luck to you and your daughter as she starts her career, and if you find any better sources, or come across the name Bernard Seidel, Detective, in your research please pass it along .