I have been getting this quite a bit recently and hope to get this pinned for future players to see.
If someone is breaking rules do not break rules to stop them, it is not your jurisdiction to take on the roll of a pseudo-mod and attempt to suppress the issue.
What you are suppose to do is gather evidence and if you don't feel up to that then why are you reading this!?
Two wrongs does not make a right, if someone is breaking the rules then follow these steps instead of taking it into your own hands!
Step 1!
Make sure you have a mod, admin or SA admin as friends on steam. Alternatively get teamspeak and poke!
This is so if they are playing something else or on another server you can poke or send em a message for assistance immediately
Step 2!
Gather and compile evidence!
Alright, if an admin is on the scene immediately after asking for assistance then disregard this step if not then continue reading! If an admin is not present, then take a video of the current situation and make sure to show the steam ID's and names of the rule breakers within the video. Create drafts of the warn/ban report as well on the forum in the report/abuse section
(!!!MAKE SURE TO FOLLOW THE TEMPLATE!!!)
Step 3!
Post and if possible have a personal talk with an admin to better convey a picture of what went down
This one does not require much explaining, aside from checking for spelling, grammar mistakes just in case!
DarkRP 1 
Discord