As in previous general elections, all votes cast on Thursday next week will be traceable - in theory - by matching serial numbers on the ballot form with the electoral roll numbers recorded by polling-station clerks on counterfoils.
This is to allow votes to be traced in cases of "personation", when someone votes claiming to be someone they are not. If personation is proved, the bogus vote can be retrieved and the genuine voter allowed to cast a vote instead.
But Liberty claims the procedure is a "serious threat to ballot secrecy", because state agencies could abuse vote tracing to find out who voted for parties of which they disapproved. "We have learned much in recent years about some of the more dubious activities of MI5," said a Liberty report on vote tracing.
"We now learn from the debates on the Police Bill that the police have also for decades been engaged in covert surveillance and telephone bugging without the knowledge or control of the responsible ministers,"the report added.
It continued: "Can we really believe that these agencies would never attempt to find out who voted for a candidate whose views they considered subversive or dangerous, when they could do so quickly and easily, in secret, with no public controversy?"
But Liberty has clashed with the Electoral Reform Society, with which it carried out a joint inquiry into ballot secrecy, published yesterday.
The ERS concluded that vote-tracing was needed to "ensure the probity of the system" by enabling abuse to be identified and corrected.
But Liberty argues that vote-tracing "does not help in the detection of electoral fraud". It simply allows the result to be corrected, if personation is proved, according to its dissenting report. This would only matter if the number of fraudulent votes were greater than the winning candidate's majority.
Liberty calls for vote tracing to be abolished and admits that it would not be possible to correct an election result if fraud were proven in a close contest. "It might become necessary to re-run a constituency's election in a very few cases - one a century, perhaps - when the winner's majority is smaller than the number of personated votes. That is a small price to pay for a truly secret ballot," says the Liberty report.
Eric Syddique, director of the ERS, disagrees. "I think they are naive. The fact that the vote-tracing rules are there is a deterrent. Remove them, and over a period of time people would work out how to carry out fraud and get away with it. And if an election is a snapshot at a particular time, a re-run election may produce a very different result."
But Liberty claims that Home Office officials have admitted that the vote-tracing provisions are no longer needed, and that they cause public disquiet. It argues that voters should still be checked off the electoral register when they vote, to prevent personation, but that nothing should be written on the counterfoils of ballot forms.
Vote tracing has been controversial since it was introduced along with the secret ballot - as distinct from public voting which preceded it - in the Ballot Act of 1872.Reuse content