Though presumably no one reading this needs the clarification, here it is anyway: No, Joe Biden did not actually hold his phone up to the mic to play an excerpt from the N.W.A megaclassic "Fuck Tha Police" at a recent campaign event.
Instead, per the Washington Post, Biden—on his first trip to Florida as a POTUS nominee—pulled his phone out to play a bit of "Despacito" following an introduction from Luis Fonsi himself at the event focused on Puerto Rican voters in the state. Naturally, the moment resulted in a swath of jokes that ultimately pushed both Biden and the 2017 song into the top trending topics on Twitter.
On Tuesday night, Trump quote-tweeted a poorly edited version of the Biden clip that unconvincingly replaced "Despacito" with the N.W.A protest anthem. At the time of this writing, the tweet had been flagged by Twitter and now carries a "manipulated media" warning.
And while the makers of the Trump-shared clip describe themselves as a "parody/satire" channel, Trump's accompanying commentary (and, obviously, his track record) doesn't make it clear whether he believed the clip to be true and/or wanted to take advantage of the general state of confusion his less Twitter-knowledgeable supporters seem to live in.
Per Twitter policy, the process for determining when to label (or even remove) manipulated content is simple:
We are most likely to take action (either labeling or removal, as described below) on more significant forms of alteration, such as wholly synthetic audio or video or content that has been doctored (spliced and reordered, slowed down) to change its meaning. Subtler forms of manipulated media, such as isolative editing, omission of context, or presentation with false context, may be labeled or removed on a case-by-case basis.