| Abbreviation | Definition |
|---|---|
| IRV | Incident Response Vehicle |
| IS | Information System |
| ISLP | Information Systems for Local Police |
| ISN | International Security Network |
| ISP | Idaho State Police |
| ISP | Illinois State Police |
| ISP | Indiana State Police |
| ISPERN | Illinois State Police Emergency Radio Network |
| ISPS | International Society of Police Surgeons |
| ISSP | Inner Solar System Police |
| ISSP | Intensive Supervision and Surveillance Programme |
| ISSP | Inter Solar System Police |
| ISSP | Inter-Solar System Police |
| ITBP | Indo Tibetan Border Police |
| ITBP | Indo-Tibetan Border Police |
| ITBPF | Indo Tibetan Border Police Force |
| ITLO | Information Technology Liaison Officer |
| ITO | Interpol Transport Officers |
| IUCR | Illinois Uniform Crime Reporting |
| IUPA | International Union of Police Associations |