A train company asked passengers for their views about plans to slash jobs and close ticket offices - but gave them unobtainable contact details.
The Rail, Maritime and Transport union says it was a sham and the redundancy consultation process should be halted.
London Midland railways want to axe 122 full time jobs, slash the opening hours at 86 out of 90 ticket offices and close nine ticket offices completely.
Posters displayed at London Midland stations asking passengers their views were found to contain incorrect contact information - making it impossible for the public to record their opinions.
The union says information about jobs and grades in the firing line has not been made available, and existing agreements on redeployment are not being followed.
RMT has warned of a ballot for industrial action if the proposals are not withdrawn.
Regional transport organisation Centro opposes the planned cuts.
Read the RMT press release with comments from Bob Crow