Clinton has spoken out about criminal justice issues and has called for reforms, including national guidelines for the use of force by police.
But early in her candidacy, Clinton was confronted by Black Lives Matter in a tense conversation offstage at one of her events. She has also been criticized for using the term "super predators" to describe violent urban youth when she was first lady in the 1990s. Clinton has since said that she regrets using that terminology.
Packnett has endorsed Clinton but other figures in the movement, like McKesson and Alicia Garza, have withheld their endorsements.
The meeting will take place on Friday ahead of a campaign event in Cleveland.