The city of Atlanta has a similar program since about 1990 called COMNET. City businesses could pay a yearly fee and were given access to a UHF conventional repeater that was monitored by APD Detective radio where they could call APD directly and officers could switch their (then on UHF conventional) radios directly to COMNET to coordinate responses.
The system was eventually patched to their 800 trunking system (analog system) when Atlanta went 800 in 1995. It also became widely abused by police impersonating unlicensed security guards who would run tags, use it as an intercom, etc. Often times Detective radio would not monitor it at all and no one would answer.
Ironically the city never bothered to get a license for the UHF repeater on 453.25MHz until 2007, after the local media was tipped off about their bootlegging (gee...wonder who did that). The repeater has been off the air since Atlanta went digital, though there is a COMNET talkgroup listed.on the new DTRS. Now COMNET users have to buy an outrageously priced digital radio to use the system.
Not practical when any cellphone that acquires a network signal can call 911 for free. Oh wait, no one answers Atlanta 911! Why bother spending money for staff when you blew it all on a brand new 911 center, CAD and radio system!