Exegesis:

hōs egeneto hēmera ‘when day came.’ In this phrase hēmera means ‘daylight,’ ‘dawn,’ cf. 6.13; Acts 27.29.

sunēchthe to presbuterion tou laou, archiereis te kai grammateis ‘the council/elders of the people met, the chief priests and the experts in the law.’ The clause may be interpreted in two ways: (1) archiereis te kai grammateis indicate of what kind of members the council was composed (cf. Phillips, Translator’s New Testament, Revised Standard Version); (2) to presbuterion is used here in the concrete sense of hoi presbuteroi ‘the elders’ (cf. New English Bible), preferably the latter. presbuterion.

sunagō ‘to bring together,’ here in the passive with reflexive meaning, ‘to meet,’ ‘to assemble,’ ‘to gather.’

apēgagon auton eis to sunedrion autōn lit. ‘they brought him before their council,’ but in view of the context here best understood as ‘they had him brought before their council.’ apagō is used here in a judicial sense.

sunedrion ‘high council,’ ‘Sanhedrin,’ highest religious and civil body among the Jews.

Translation:

When day came, see on “when it was day” in 4.42.

The assembly of the elders of the people gathered together, both chief priests and scribes, preferably, ‘the elders of the people, chief priests, and scribes came together,’ mentioning some of the officials found also in vv. 2 and 52. For the people, here referring to the Jewish nation, see on 1.17.

Their council, i.e. the council formed by them, or, of which they were members. For council cf. ‘place for speech-making/discussion’ (Ekari), ‘great assembly’ (Tae’), or more juridically, ‘(high) tribunal’ (Sranan Tongo, Bible de Jérusalem, Javanese), ‘assembly of their Judgment-court’ (Marathi).

Quoted with permission from Reiling, J. and Swellengrebel, J.L. A Handbook on the Gospel of Luke. (UBS Handbook Series). New York: UBS, 1971. For this and other handbooks for translators see here . Make sure to also consult the Handbook on the Gospel of Mark for parallel or similar verses.