Seventeen Labour Party members have been asked to answer charges of electoral fraud.
An election commissioner invited activists to answer allegations of corrupt and illegal practices during council elections.
Six Labour councillors in Birmingham have been accused of abusing postal votes in the 2004 poll.
Deputy High Court Judge Richard Mawrey QC has finished hearing the second of two petitions lodged against the six.
He said he had a duty to identify all persons guilty of such offences.
Their names, he said, would be included in a report sent to the House of Lords for consideration following the trials, with the result that they could be barred from voting or standing for election for the next five years.
Mr Mawrey said a "considerable body of evidence" had been presented during the first petition, brought by the People's Justice Party against Labour councillors in Bordesley Green, showing that Declarations of Identity forms, which accompany postal ballot papers, had been forged.
The judge served notice on 17 Labour Party members and two other people related to one or other of the Labour councillors, under the Representation of the People Act 1983.
He said: "I am giving them the opportunity to appear before me today to show cause why I should not name them in the report."
Mr Mawrey said he was invoking a legal process which was probably last used in the 1890s.
Sixteen of the 19 people notified of proceedings were represented in court on Monday.
The judge, who is presiding over the hearing at the Birmingham and Midland Institute, will start hearing evidence in each case on Tuesday.