Senorise Perry has every right to wear number 32 with the Buffalo Bills. O.J. Simpson’s jersey number is available and was never retired in Buffalo.
It may have been an unofficial rule under the Wilson family ownership before the murder trial in 1994, onset in 1977, that no one would be given that jersey number. Following the murder trial, it was probably just a topic no one chose to address and just left that number alone.
I am sure if some big-name running back equivalent of wide receiver Terrell Owens signed as a free agent and 32 was his lifetime number, the number 32 would have been worn many seasons ago.