What constitutes a critical incident?
Any sudden event involving a police officer that results in an immediate investigation with no advanced notice to the subject officer and potentially resulting in the arrest, suspension, or termination of the subject officer.
Examples:
- Officer involved shootings
- In-custody deaths
- Use of force/weapons discharge (including less-than-lethal force)
- Car accidents
- Any allegation of duty-related criminal conduct
4 Things you NEVER do:
- NEVER give a voluntary statement
- NEVER take a polygraph
- NEVER give blood or urine
- NEVER talk to crisis response team, victim advocate, debriefing team, peer groups, or anyone unless you have a legally confidential relationship with that person.
Things you should always do when involved in a critical incident:
- Secure the scene and preserve evidence
- Notify the dispatcher and appropriate supervisor(s)
- Notify EMS
- Contact your FOP attorney and
- REMAIN SILENT
Things you should always if you are an uninvolved officer at the scene of a critical incident:
- Make sure the involved officer is OK
- Assist involved officer in contacting FOP attorney
- Stand by the involved officer until his/her representative/attorney arrives
- Do NOT talk about the facts with the involved officer
- Provide the representative/attorney with as much information as possible
- Remind the involved officer to REMAIN SILENT
Source: NFOP Labor Services
Signal 108 
it is coming to this, police work is no more fun,to many roadblocks, i remember the gool ole dayas