Sinn Fein must tell voters about an internal party database on their canvassing and electioneering material, the Data Protection Commission has said.
A report published on Monday by the Data Protection Commissioner says that the Abu database is a "specially designed, bespoke relational database that was designed to identify supporters in order to get out the vote on election day".
"The system contains data from the register of electors and the marked electoral register and is supplemented by canvass information."
Under data protection rules, it said that the party should now "proactively" tell voters that the database exists and that this practice should continue as long as the database continues to exist.
The review by the Data Protection Commissioner came after media reports earlier this year on the alleged use of an internal database by the party for the storage of the personal information of voters.
The report, after assessing and reviewing the practice by Sinn Fein in the Republic, notes "that the sample canvassing literature made no reference to the Abu database or to the fact that canvassing information with regard to prospective voters to whom the leaflet is handed out may be processed on the Abu database".
The Data Protection Commissioner carried out audits of how all Irish political parties process voters' data.
In the case of Sinn Fein, the commissioner report notes that the total number of eligible voters marked as to their political opinions is around 5.85% of the overall number of voters on the database.
It also found that: "Abu does not contain records of individuals in Northern Ireland or elsewhere and it is not used by officers or offices of Sinn Fein in Northern Ireland."
The same report reveals that Fianna Fail, Fine Gael and the Green Party were instructed to update their privacy policies regarding the use of electoral registers.
