Post History

How did "join issue" mean ‘jointly submit a disputed matter to the decision of the court’?

Kindly see the embolded phrase below. [Etymonline](https://www.etymonline.com/search?q=issue)  is written too abstrusely. 
>### issue [13] 

>The words *issue* and *exit* are closely
related etymologically. Both go back ultimately
to the Latin verb *exīre* ‘go out’. Its past participle
*exitus* became in Vulgar Latin *exūtus*, whose
feminine form *exūta* was used as a noun
meaning ‘going out, exit’. This passed into Old
French as *eissue*, later *issue*, and thence into
English. The original literal sense of the word
still survives in English, particularly in relation
to the outflow of liquid, but has been overtaken
in frequency by various metaphorical extensions
denoting a ‘giving out’ – such as the ‘issue’ of a
book or magazine. The sense ‘point of
discussion or consideration’ probably comes
from a **medieval legal expression *join issue*,
which originally meant ‘jointly submit a
disputed matter to the decision of the court’**, and
hence ‘argue about something’.

*Word Origins* (2005 2e) by John Ayto. p 292 Right column.