Neither the Magistrates nor the Titans are the "RP Police". No one can "invalidate" someone else's RP, whatever that means. If you think they broke an IR or term of the Social Contract, then you can report to the Titans or Magistrates. (The Magistrates are probably a better choice for non-multi issues.)
Other than that, feel free to counter-RP whatever you want, within the limits of good RP.
