ACFT 1 HAD GND CONFLICT WITH ACFT 2 IN NON MOVEMENT AREA OF RAMP.

Narrative

I AM AN ATC TRAINEE AT THE AURORA (ARR) CTL TWR. I HAVE BEEN HERE ABOUT 3 MONTHS. I WAS TRAINING ON GND CTL AT THE TIME OF THE INCIDENT. ACFT #2 HAD EXITED THE RWY AND I HAD INSTRUCTED IT TO TAXI TO THE RAMP. SHORTLY AFTER THAT; ACFT #1; LOCATED ON THE W RAMP; CALLED FOR TAXI TO THE ACTIVE. I TAXIED ACFT #1 TO THE ACTIVE; AFTER ASCERTAINING THAT ACFT #1 AND ACFT #2 WOULD NOT CONFLICT ON A MOVEMENT AREA. SHORTLY AFTER THAT; ACFT #2 CALLED UPSET. HE AND ACFT #1 WERE NOSE-TO-NOSE ON THE W RAMP. I TOLD ACFT #2 THAT I WAS NOT RESPONSIBLE FOR NON MOVEMENT AREAS; AND THAT THE ENTIRE RAMP AREA WAS NON MOVEMENT. HE CONTINUED TO INSIST THAT I SHOULD HAVE TOLD HIM HOW TO AVOID ACFT #1. ACFT #1 CHIMED IN AND AGREED. I FEEL THAT PLTS AT AURORA HAVE COME TO EXPECT US TO CTL THEM ON THE NON MOVEMENT AREAS. THIS IS DUE TO THE FACT THAT WE HAVE A SUPVR HERE THAT INSISTS THAT WE CTL ACFT ON THE RAMPS. THIS HAS LED LOCALLY BASED ACFT TO EXPECT CTL INSTRUCTIONS ON NON MOVEMENT AREAS. I FEEL THIS COULD LEAD TO AN UNSAFE SITUATION IN THAT 2 ACFT ON NON MOVEMENT AREAS MIGHT EXPECT US TO KEEP THEM APART AND AS A RESULT NOT EXERCISE DUE CAUTION. I FEEL WE SHOULD STOP THE PRACTICE OF ISSUING CTL INSTRUCTIONS TO ACFT ON NON MOVEMENT AREAS AND ISSUE A LETTER TO AIRMEN REF ENFORCING THE FACT THAT PLTS ARE RESPONSIBLE FOR THE SAFETY OF THE RAMP AREAS.