WHILE BEING VECTORED FOR AN ILS RWY 7 APCH, THE PLT WAS TOLD TO MAINT 3000' & ADVISED HE WAS FLWG A BOEING 727. THE MIN APCH ALT BFR INTERCEPTING THE ILS GLIDE SLOPE (G/S) AT THE FINAL APCH FIX/OUTER MARKER (OM) WAS 1900'. AS THE ACFT WAS APCHG THE OM, THE PLT WAS CLRD FOR THE APCH & WAS HANDED OFF TO THE TWR. AFTER CONTACTING THE TWR, THE PLT WAS TOLD TO DSCND AS PUBLISHED. AT APRX THAT TIME, THE TWR CONTROLLER (CTLR) & HIS SUPERVISOR DISCUSSED N700CM'S ALT & PROXIMITY TO THE 727. THE CTLR WAS GOING TO DISCONTINUE THE APCH, BUT HIS SUPVR SUGGESTED HE WAIT & SEE IF IT WOULD WORK OUT. SUBSEQUENTLY, N700CM CRASHED INTO TREES APRX 5800' SHORT OF THE RWY WHILE DSCNDG IN A WINGS LVL ATTITUDE. RADAR DATA SHOWED N700CM WAS WELL ABV THE ILS G/S WHEN CLRD FOR THE APCH. ATC PROCEDURES REQD THE ACFT TO BE BLO THE G/S BFR BEING CLRD. ALSO, N700CM WAS APRX 2.57 MI BEHIND THE 727, BUT STAYED WELL ABV THE 727'S FLT PATH (& POSSIBLE WAKE TURBULENCE) UNTIL MOMENTS BFR IMPACT. N700CM ENTERED AN EXCESSIVE RATE OF DSCNT BFR GOING BLO THE G/S.