Dzu and other opposition candidates alleged electoral fraud after the poll, but he was arrested after the election on grounds of making illicit currency transactions and jailed by a military court for five years of hard labor.

[4] One of Dzu’s law partners was good friend Nguyễn Hữu Thọ, who later left Saigon and went into the countryside to become the nominal political leader of the National Liberation Front, as the Vietcong called itself.

[4] Dzu also worked in law with Trần Văn Khiêm, the younger brother of Madame Nhu, the First Lady and sister-in-law of bachelor President Ngô Đình Diệm.

[3] Dzu had declared his intention to stand as a candidate for the 1961 South Vietnamese presidential election against President Diem, but he was intimidated into withdrawing after being accused of having engaged in illegal fund transfers out of the country.

[2] In early-1967, several Americans who were detained on currency-violation charges, something that was routine in South Vietnam, accused Dzu of offering to have them released if they gave him a commission of USD10,000 to bribe the judges.

[4] While others also advocated peace deals, Dzu was the most vigorous in disseminating his message,[4] making competitors such as the aged Phan Khắc Sửu and Trần Văn Hương, who had briefly served as president and prime minister respectively under the junta's supervision in 1964–65, appear lethargic.

[4] Along with two other failed presidential candidates, Sửu and Hoàng Cơ Bình, Dzu held a media conference accusing Thiệu and Kỳ of engaging in election fraud.

[6] American officials, in line with their support for Thiệu and Kỳ, dismissed the protests as sour grapes, but a committee from the Constituent Assembly later resolved 16–2 to void the election results due to "a pattern of fraud".

[2] Dzu was arrested and brought before a Special Military Court on 26 July 1968 and sentenced to five years of hard labour, but due to public pressure in South Vietnam and abroad, he was released after only five months.

[2][8] Other sources said he was invited by the new government to serve as a senior adviser in Hanoi, where he lived in Từ Liêm district and later died in Ho Chi Minh City c. 1991.