He started his education at the college of Ath and completed high school in Dijon, under the direction of the famous Joseph Jacotot (1770–1840), his uncle by marriage.

He played an important role in this memorable assembly due to his great knowledge of the law, his elegant elocution and his irresistible logic.

When Surlet de Chokier was elected regent of the kingdom, Defacqz was named secretary-general with the ministry of Justice.

In 1850 he became honorary member of the Masonic Lodge Minerva zu den drei Palmen Leipzig.

He published in particular: In 1845, the Flemish musician and freemason Charles-Louis-Joseph Hanssens composed in 1845 a cantata for Eugene Defacqz.