BUR #26941 has been rejected.
remove implication phoenix_wright:_ace_attorney -> ace_attorney
create implication phoenix_wright:_ace_attorney -> phoenix_wright:_ace_attorney_trilogy
remove implication phoenix_wright:_ace_attorney_-_justice_for_all -> ace_attorney
create implication phoenix_wright:_ace_attorney_-_justice_for_all -> phoenix_wright:_ace_attorney_trilogy
remove implication phoenix_wright:_ace_attorney_-_trials_and_tribulations -> ace_attorney
create implication phoenix_wright:_ace_attorney_-_trials_and_tribulations -> phoenix_wright:_ace_attorney_trilogy
create implication phoenix_wright:_ace_attorney_trilogy -> ace_attorney
category phoenix_wright:_ace_attorney_trilogy -> copyright
These games are frequently grouped together since they all depict Phoenix Wright's first few years of lawyering. Capcom themselves also sell the trilogy as one game nowadays. The appearances of recurring characters are also consistent, like Maya Fey, Mia Fey, Larry Butz, etc.
Capcom now sells the next trilogy (Apollo Justice: Ace Attorney, Dual Destinies, Spirit of Justice) as a set as well, but they're hardly as connected as the first three are, so I'll leave them out of the umbrella tag treatment for now.
Updated