Reverse mechanism of service tax

Please clarify even if call taxi excluded what is calling call taxi is there any definition given because call taxi may be some person having audhtorised/registered some persons drived occussionaly clarify exactly the same please

Thanks in advance

"metered cab" means any contract carriage on which an automatic device, of the type

and make approved under the relevant rules by the State Transport Authority, is fitted

which indicates reading of the fare chargeable at any moment and that is charged accordingly

under the conditions of its permit issued under the Motor Vehicles Act, 1988 and the rules made

thereunder;

Call taxis, radio taxis are included in this defiinition.  The services on these vehicles are exempted in section 66D of the negative list.

Dear sir,

pls clarify a doubt on reverse mechanism.If a service provider gives service tax msitakenly instead of service receiver under reverse mechanism ,will service receiver be exempt from paying the service tax liability?