For a cold case, the questions I have would be:
- What happens to the case files for a cold case -- how long are the records kept? (my guess would be that the NYPD would hold on to the case files as long as the case was still open, but the only way to find out is to ask) and
- Could a file from 1907 be requested via the FOIL? (for information on how to do that, see the end of the answer).
Your best bet may be to start with the FOIL officer at the NYC Archives.
In the midst of looking up the answer to this question, I forget that you said this was an unsolved homicide, and wrote an answer about someone looking for a case which had been solved (thus the links to court records). I'll leave that in place in case the links might help someone else. But for an unsolved case, even if you can't get the detectives' case files, you might be able to get some records from the Municipal Archives' collection of records from the Coroner and Office of Chief Medical Examiner, 1823-1950.
My general records-gathering checklist is:
- Learn what records might have been created in a particular time and place.
- Research which of those records might still exist, and which records are accessible to the public.
- Research what repositories might hold those records.
- Research which online repositories might hold those records.
For a crime that takes place today, you can ask the NYPD's Record Inquiries | Criminal Records Section whose website says:
The Criminal Records Section stores and maintains reports of crime and
lost property, and provides information from these files to members of
the public and authorized agencies, as required by law and Department
The Criminal Records Section is NOT open to the general public.
The information on that page is not for requesting the casefile, but for a verification report. These are for getting an official record of crimes or lost property (e.g. if you car or house is broken into, you may need an official record of the crime to submit to your insurance agency).
You could try calling the telephone inquiry line and asking:
- if these verification reports are for property crimes only, or do they generate reports for assaults and homicides and
- if they do produce reports for assaults and homicides, how far back do their records go?
- Ask if they deal with FOIL requests (see below), and if not, who does?
For a crime that took place in 1907, they will probably send you to the NYC Archives. Usually the amount of time that records need to be kept is determined by state statute. Statues can be looked up online (if I find the link, I'll come back and drop it in here). After that, there's usually a procedure they have to follow which says that the records either have to be destroyed or turned over to some other agency.
Your next stop might be the website of the New York City Department of Records to see what material might be in the Municipal Library or the Municipal Archive.
The Municipal Library offers Research Guides on various topics including:
At the Municipal Archives, their Collections page lists:
I don't know if the actual NYPD Casefiles are archived, and if so, if you could get copies of those records, but you could try making a FOIL request. Look for the question How can I submit a FOIL Request to the NYC Department of Records and Information Services? on the FAQ Page for the contact information for the FOIL officer. General information about the Freedom of Information Law can be found at the New York State's Committee on Open Government website. See Access to Agency Records.
Any dates you can glean from your death certificate or other NYC records could be a springboard to research in newspapers, or newspapers could provide clues for what dates to search for records. I found a probate record because of a series of newspaper articles that had been published about the dispute over the estate.
Also check with the New York Public Library, which holds the case files for the Honorable Gustav Scholer, head Coroner for the city of New York.
See the article:
Peek Inside the Grisly, Salacious Case Files of NYC's Head Coroner in the Early 1900s
Responsible for investigating the city's suspicious deaths, and
examining the mental pathologies of accused criminals who claimed
insanity, Scholer meticulously kept and filed away his murder case
notes, autopsies, newspaper clippings, psychiatric profiles, unclaimed
personal affects of the deceased and anonymous tip-off letters such as
the one he received concerning Mrs. Todd.
Scholer's widow donated the case files to the NYPL after his death. The catalog description and Collection overview: Gustav Scholer papers 1855-1929 [bulk 1887-1920] says that he held the post of coroner until 1905, which is too early for your case if the 1907 date is correct.
However, if you can find out who followed Scholer as coroner, you could look for a similar manuscript collection at the New York City archives or elsewhere by searching on ArchiveGrid.
If you can't find the actual case files, try looking for a copy of the Coroner's annual report to the mayor for 1907.