also returning to this, The Secret Agendas anthology book has a short stories acting as a prequel to the season 10 comics...
So leading into both seasons 10 and 11 being canon. But again, we'll see.
Fontana-Wolf universe
The Fontana-Wolf universe contains series that aired primarily on NBC. Tom Fontana wrote and produced many television series and connected them with various crossovers. Dick Wolf is the creator of the Law & Order and Chicago franchises. Fontana and Wolf brought their two universes together through several crossovers between Homicide: Life on the Street and Law & Order. Dick Wolf brought Richard Belzer, playing John Munch, over to Law & Order: Special Victims Unit from Homicide: Life on the Street.
Tom Fontana series
St. Elsewhere (1982) It was created by Joshua Brand and John Falsey, but Tom Fontana wrote or co-wrote 93 out of 137 episodes.
Homicide: Life on the Street (1993) It was created by Paul Attanasio, but Tom Fontana wrote or co-wrote 67 out of 122 episodes for the series.
Oz (1997)
The Beat (2000)
Dick Wolf series
Law & Order franchise
Law & Order (1990) has seven in universe crossovers.
Law & Order: Special Victims Unit (1999) has nine in universe crossovers.
Law & Order: Criminal Intent (2001) has three in universe crossovers.
Law & Order: Trial by Jury (2005) has two in universe crossovers.
Conviction (2006) spun off from Special Victims Unit and has one in universe crossover.
Law & Order: LA (2010)
Foreign adaptations
Paris enquêtes criminelles]] (2007)
Law & Order: UK (2009)
Chicago franchise
Chicago Fire (2012) has nine in universe crossovers.
Chicago P.D. (2014) spun off from Fire with the backdoor pilot "Let Her Go" and has nine in universe crossovers.
Chicago Med (2015) spun off from Fire with the backdoor pilot "I Am the Apocalypse" and has two in universe crossovers.
Chicago Justice (2017) spun off from P.D. with the backdoor pilot "Justice" and has two in universe crossovers.
Other Wolf series
New York Undercover (1994) has two in universe crossovers.
Deadline (2000) has had no direct in universe crossovers, however its fictional New York Ledger appears in any series based in New York City.
Reality series
Arrest & Trial (2000)
Crime & Punishment (2002)
Law & Order True Crime (2017)
Other series
In Plain Sight (2008) has one in universe crossover. It was created by David Maples and aired on the USA Network.