| December 1949 |
Robert Menzies (Lib) defeated Ben Chifley (ALP) in federal election. |
| April 1950 |
Menzies introduced the Communist Party Dissolution Bill. |
| October 1950 |
Communist Party Dissolution Bill passed through Parliament. |
| October 1950 |
Communist Party challenged the Bill as unconstitutional. |
| March 1951 |
High Court found the Bill to be unconstitutional by a vote of 5 to 1. |
| April 1951 |
Double dissolution followed by an election returning Menzies to power. |
| September 1951 |
Referendum to allow Commonwealth Government to ban Communist Party was narrowly defeated. |
| April 1954 |
Russian spy Vladimir Petrov and his wife defected to Australia and revealed information about a spy network operating in Australia. |
| May–June 1954 |
Election campaign – main issue was communism. Menzies was returned with a reduced majority. |
| August 1954 |
Report of the Royal Commission into the Petrov affair. |
| February 1955 |
ALP split over fears of communism. DLP (Democratic Labor Party) was created. |
