Justin Bieber -- Judge to Conduct Penile Investigation

Justin Bieber is about to make a judge's daughter the envy of her schoolmates, because he's about to see Justin's junk.

According to new court docs, Bieber's wiener and/or backside -- as they appear on jail surveillance footage following his DUI arrest -- will be carefully examined in private by prosecutors AND a judge ... before any more Bieber jail videos are released to the public.

TMZ broke the story ... Bieber's attorney asked the court to

Bieber's camp claimed additional jail footage features the singer's "intimate personal parts" -- which we've learned Bieber accidentally revealed while urinating in his holding cell -- and they want to keep the videos under lock and key.

Now, prosecutors have responded, agreeing to hold off on the release of any more embarrassing footage -- pending review by a judge.