You may want to seek help from an attorney in your area on the matter.  Generally, you can access many public records through the Freedom of Information Law (FOIL) but if this file with your name on it is part of an ongoing investigation I do not see how you are going to obtain a copy unless and until you are brought up on charges and the matter goes to the prosecutor's office.  Then there are discovery rules that run in the favor of the defendant that will grant you access to the information you claim was collected by the police.  But ask a criminal attorney in your area just in case.  Good luck.