According to linguist Viljo Nissilä, the name of the lake may refer to local court hearings regarding hunting grounds, as minor conflicts such as theft were often settled by the place where they had happened.

[5] Tuomiojärvi is located in the Kymijoki main catchment area and is part of its second-order Päijänne basin.

[7] Other inflows include Eerolanpuro, which begins from the industrial area of Rautpohja, flowing through the pond Vehkalampi in Kortepohja before discharging into the Eerolanlahti bay in the southern part of the lake.

[6] Tuomiojärvi itself discharges into Palokkajärvi via the short Löylyjoki river, which flows under the national road 4 in Taulumäki.

[2] Lehtisaari is owned by the parish of Jyväskylä (Jyväskylän seurakunta), which operates a public sauna on the island.

[9] The Rautpohja (also called Rautpohjanlahti) and Eerolanlahti bays in the southern part of the lake have been designated as Natura 2000 zones, covering a combined area of 43 hectares.

[11] The colony grew significantly in the 2010s as the Killervä [fi] (also called Killerjärvi), a small lake in the middle of the Killeri horse racing track further west was dredged to remove gull nests.