Same-sign tri-leptons with a left-sneutrino as the lightest minimal supersymmetric particle

Assuming that $SU(2)_L$ doublet sneutrinos are the lightest among the MSSM sparticles, we show that it is possible to obtain same-sign tri-lepton (SS3L) events in the R-parity conserving supersymmetric scenarios. We consider the cascade decay of the lightest stop or the gluino above it to the lightest sneutrino via an intermediate on-shell gaugino--like neutralino and/or chargino and show that such processes can lead to SS3L events. We discuss the prospect of observing these SS3L events at Large Hadron Collider (LHC) and comment on discovering or constraining the proposed spectrum from future LHC data.