The PAC said that regional systems that offered an integrated service to all three emergency services would have been cheaper. It also warned that it was not clear who would be responsible if health fears surrounding the system are justified. Some police officers have claimed that using Airwave handsets made them ill.
The report noted that the £1.5bn Airwave voice and data network "might be more sophisticated and expensive than it really needs to be", but added that it did offer a high degree of interoperability between police forces across the country.
It also highlighted the reluctance of local forces to adopt the system, which was commissioned by the Police Information Technology Organisation in 2000 from O2, British Telecom's former mobile telecoms arm.
"Throughout the procurement, police authorities expressed doubts about whether Airwave was affordable," the PAC noted.
To persuade reluctant police authorities to adopt Airwave the Home Office "decided at a late stage to pay police authorities some £500m to finance the deal over the first three years," according to the report.
The Terrestrial Trunked Radio (Tetra)-based system is used by seven police forces around the country and will be rolled out to all 53 forces by the end of 2005.
It is almost 10 years since the Home Office recommended a joint police and fire service radio system, but the PAC noted that the Government had not convinced the other emergency services to adopt Airwave.
In the aftermath of last year's terrorist attacks the Government is making a renewed effort to get all the emergency services onto a common platform.
Last month, British Transport Police, Lancashire Fire and Rescue Service and the Ministry of Defence adopted the system. The Government is planning to issue tender notices for similar network provision for the ambulance and fire services, which emphasise interoperability.
O2 is keen to promote its Tetra technology but the other emergency services are believed to prefer a system based on the rival Tetrapol system.