Is a police officer, when he/she is the first to find a dead person, questioned, just like any other person would be?

I have read that, for example, when a child is killed, it is custom to also question the possible involvement of the parents and/or siblings (especially if they are the ones that discovered the body).
Now, if a police officer, on duty, finds a deceased person, and reports it, is he/she also questioned (or is his/her possible role investigated by detectives (with or without him/her knowing))?
Or is a police officer not suspected in first instance?