The Diddy trial is going to spend a lot of time on his "Freak Off" parties, and the issue here is consent ... his defense says the encounters were consensual, and the prosecution needs to prove otherwise.

TMZ examines the legal strategy surrounding the Freak Offs in our new documentary, "The Downfall of Diddy: His Defense," available now on Tubi.

Criminal defense lawyers who have won some of the most high-profile celebrity criminal cases in America break down how consent will play a big role in Diddy's trial.

Prosecutors need to prove Diddy used coercion in those Freak Off parties if they're gonna get a conviction -- but listen to Joe Tacopina, Mark Geragos and Jose Baez explain why Diddy's defense will be confident they can prove these were consensual encounters.

Diddy's team describes all the alleged victims as former girlfriends ... and as these criminal defense lawyers point out, it's no easy task for the feds to convince a jury these women were being sex trafficked.

We even had a mock jury for our documentary, which deliberated and fiercely debated coercion and consent ... before voting on whether Diddy is guilty or not.

"TMZ Presents The Downfall of Diddy: His Defense" is available for free on Tubi.