[3] The group advocated the abolition of private property, the ownership by the workers and labourers of the means of production and the assimilation of Ireland into a Federation of Socialist Republics once World War II had ceased.

Some names associated with the group included John de Courcy Ireland, RN Tweedy and Frank Edwards.

[4] The Vanguard's blazen communistic rhetoric quickly made the group a target for the new National Labour Party as well as the Catholic Church.

[4][6][7] Cowan supported Noël Browne over the Mother and Child Scheme and stood again as an Independent candidate at the 1951 general election where he retained his seat.

It was during this period that Cowan represented (pro bono) the family of a young Eamon Dunphy who were faced with eviction.

On 1 November 1957 Cowan was convicted of embezzling £3,705 from a bricklayer, James O'Reilly and was sentenced to 2 years of prison.

After an appeal to the Supreme Court failed, Cowan was struck off the roll of solicitors by the chief justice on 31 October 1958.

One of those sons, Rory Cowan, unsuccessfully contested the Dublin North-East constituency for the Labour party in 1965.