[5][6][7] Long was co-counsel in the investigation and prosecution of celebrity bandleader Irvin Mayfield, and of his business partner Ronald Markham.

[2] Nine members of the Congressional Black Caucus wrote a letter[10] to President Joe Biden asking him to withdraw the nominations of Long and Jerry Edwards Jr. because the sole Democratic lawmaker from Louisiana, Representative Troy Carter, had not been properly consulted on multiple judicial nominations.

President Biden nominated Long to the seat vacated by Judge Martin Leach-Cross Feldman, who died on January 26, 2022.

[16] During his confirmation hearing, Republican senators, including Senator Josh Hawley, pressed him on his role as deputy chief of staff to FBI Director Christopher Wray from 2020 to 2021 regarding a federal investigation of Hunter Biden and other allegations about the Justice Department that have angered conservatives.

[17][18] On July 12, 2023, U.S. Representative Steven Horsford sent a letter[19] to Senate Judiciary chairman Dick Durbin saying the Congressional Black Caucus would oppose the Senate Judiciary Committee's consideration of Long, pending changes to the committee's "blue slip" policy.