An MP has given his backing to three ambulance staff suspended after information was passed to the BBC.
Control room logs suggested ambulances from Shropshire were being sent to help in Birmingham and the Black Country.
Three staff were then suspended by West Midlands Ambulance Service as part of an investigation into a possible breech of the Data Protection Act.
Daniel Kawczinsky, MP for Shrewsbury and Atcham, said he was worried staff were being "intimidated".
It comes amid concerns over plans to close the ambulance control room in Shrewsbury and instead have two centres in Stafford and the Black Country.
'Not democratic'
He said: "These issues are of fundamental importance to my constituents and the people of Shropshire and they should be aired.
"I personally am deeply concerned that people are being intimidated in this way. It is absolutely scandalous.
"I don't want to live in a society where people who provide frontline services to my constituents [and] who have genuine concerns or fears about safety issues cannot and... are not allowed to speak out.
"That's not a democratic society and that's why I will fight tooth and nail for their right to do this."
He said he was writing to Health Secretary Alan Johnson about his concerns.
West Midlands Ambulance Service has said it was concerned that patient confidentiality had been broken by the leak but has refused to comment further until an investigation is completed.
It has written to the BBC asking reporters to reveal the source of the documents passed to the corporation.
The BBC has refused to do this, saying it is not prepared to reveal confidential sources.