He was Counsel for the New York State Interdepartmental Task Force on Youth and Juvenile Delinquency in 1958.

In 1985, Sweet ordered Universal to pay Nintendo $1.8 million for "legal fees, photocopying expenses, costs incurred creating graphs and charts, and lost revenues."

However, later the Second Circuit reversed his decision and allowed Special Prosecutor Patrick Fitzgerald to access phone records of New York Times journalists.

[12] In an interview with PBS, he said that the mandatory minimum sentence for drug offences violates due process and separation of powers.

''[14] With co-author Edward A. Harris he contributed a chapter[15] to Jefferson Fish's book How to Legalize Drugs.

[17][18] In 2017 – at the age of 94 – Judge Sweet presided over the lawsuit by Virginia Giuffre against Ghislaine Maxwell.

[19] In his order on Maxwell's Motion to Dismiss under Federal Rule of Civil Procedure 12(b)(6), Judge Sweet refuted Defendant's argument that libel per se doctrine did not apply to Giuffre in her capacity as a non-profit professional.

Judge Sweet noted in dicta that, not only is non-profit administration indeed a valid profession, judicially noticeable press articles refuted Defendant's argument that denial of an individual's claim to be a victim of human trafficking does not harm them in their professional capacity as an advocate for victims of trafficking.