  Contrary to common expectation, a left-sneutrinos can occasionally be the
lightest supersymmet- ric particle. This has important implications in both
collider and dark matter studies. We show that same-sign tri-lepton (SS3L)
events at the Large Hadron Collider, with any lepton having opposite sign
vetoed, distinguish such scenarios, up to gluino masses exceeding 2 TeV. The
jets + M ET signal rate is somewhat suppressed in this case, thus enhancing the
scope of leptonic signals.
