Van Ness was nominated by President
James Madison on May 25, 1812, to the
United States District Court for the District of New York, to a new seat authorized by 2 Stat. 719. His service terminated on September 6, 1826, due to his death in New York City.
Embezzlement investigation In 1818, the clerk of Van Ness' court, Theron Rudd, who had also worked for Judge
Matthias B. Tallmadge was accused of embezzling more than $100,000 (about $1.6 million in 2019) intended to pay court judgments. Upon being discovered, Rudd fled with the money. The investigation into Rudd's theft also considered the issue of Tallmadge's and Van Ness' culpability. The friction between them was largely responsible for the split of New York's district court into southern and northern districts in 1814. Tallmadge was assigned to the northern district, but his frequent ill health often required Van Ness to preside over both courts. The investigation considered whether Van Ness and Tallmadge were failing to capably perform their duties. The committee determined in February 1819 that Tallmadge had not always held court for the northern district on the dates required by law, but that this was not an impeachable offense. The committee took no further action, and Tallmadge's continued illness caused him to resign in July 1819. ==Family and estate==