He was a law clerk to Judge Charles Grisbaum of the Louisiana Fifth Circuit Court of Appeal from 1985 to 1987.

He was in private practice in Louisiana from then until 2001, first at the law firm of Little & Metzger and then at Hailey, McNamara, Hall, Larmann & Papale LLP.

He was nominated to the seat being vacated by Judge Edith Brown Clement, who had announced her intention to assume senior status upon the confirmation of her successor.

[5] On January 3, 2018, his nomination was returned to the President under Rule XXXI, Paragraph 6 of the United States Senate.

[6] On January 5, 2018, President Donald Trump announced his intent to renominate Engelhardt to a federal appellate judgeship.