Legislative history refers to the documents created in the course of the legislative process for a particular law. They are used, in part, to understand the legislative intent behind the law. – taken from the NYU Law library's research legal research guide
For more information on legislative history and New York legal research visit the following links:
New York State Library: The Legislative History of a New York State Law: A Tutorial and Guide to Library Sources
New York State Archives: Legislative Bill and Veto Jackets
NYU Law Library: New York Legal Research: Legislative History
Bill Jacket: A Bill Jacket includes the legislative history of a bill that has been enacted into law or vetoed by the Governor. Bill jackets include the bill, the bill's sponsor memo, approval or disapproval memos, financial analysis (if necessary) and other memos, letters or comments that were submitted to the Governor's office regarding the bill. This would include comments by other agencies, organizations, or individuals. A bill jacket is an excellent resource when doing research on an issue and can be accessed through the New York State Library or by contacting the Legislative Secretary to the Governor's Counsel (for bills form the current year). – taken from the New York State Legislative Process Glossary of Frequently Used Phrases.