Your out of pocket expenses for your unpaid position as a reserve police officer could qualify as a charitable contribution. These would be entered as cash contributions on Schedule A, Itemized Deductions.
For more information see the out-of-pocket expenses section of the following IRS document: https://www.irs.gov/publications/p526/index.html
See the TurboTax article below for instructions to enter your expenses as a charitable contribution.
