Exegesis:

heistēkeisan de hoi archiereis kai hoi grammateis eutonōs katēgorountes autou ‘the chief priests and the experts in the law stood there, vigorously accusing him.’ heistēkeisan at the beginning of the clause is emphatic and stresses the action denoted by the subsequent participial phrase.

eutonōs ‘vigorously,’ ‘vehemently,’ referring either to the content of the accusation, or to the tones of their accusing, preferably the latter.

Translation:

Stood by … accusing him, cf. also, “stepped forward and pressed the case against him…” (Good News Translation).

Vehemently, or, ‘with violent words,’ ‘speaking/shouting violently.’

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.