A lobby group campaigning against same sex marriage in Australia has sparked a furore within the NSW Liberals after it was accused of improperly using confidential internal membership email lists to drum up donations and support.

Marriage Alliance, whose spokeswoman is lawyer and Liberal Party member Sophie York, sent a mass email to NSW Liberal members on Tuesday.

An image from the email sent to Liberal Party members by Marriage Alliance.

The move has sparked complaints to the alliance, the NSW Liberal Party head office and privacy groups – and accusations that the list was provided by Walter Villatora, who is running against former Federal Parliament speaker Bronwyn Bishop for preselection in the seat of Mackellar.