Title: Jack McCoy
Content:  John James McCoy is a fictional character in the television drama Law & Order. He was created by Dick Wolf and Michael S. Chernuchin and portrayed by Sam Waterston from 1994 until the end of the series in 2010. He is the second-longest tenured character on the show (16 seasons), after Lt. Anita Van Buren (17 seasons; portrayed by S. Epatha Merkerson). He appeared in 368 episodes of Law & Order, four episodes of Law & Order: Special Victims Unit, two episodes of Law & Order: Trial by Jury, two episodes of Homicide: Life on the Street, and the made-for-TV movie Exiled. Waterston's performance as McCoy on the New York–based series was so popular that it resulted in him being declared a "Living Landmark" by the New York Landmarks Conservancy, along with fellow longtime series cast member Jerry Orbach (who portrayed the popular police detective Lennie Briscoe for almost 12 years).
Title: Jack McCoy
Content:  McCoy has appeared in four episodes of Law & Order: Special Victims Unit; however, he is often referred to in the series, and his actions affect the ADAs working with the Special Victims Unit.
Title: Jack McCoy
Content:  In the opening episode of season 20, McCoy is revealed to have won the election; he serves as DA for the remainder of this final season of Law & Order. Law & Order ceased production in 2010, but McCoy (though not seen) was still occasionally mentioned as being the Manhattan DA in the spin-off series Law & Order: Special Victims Unit in several episodes through 2011. A reference to "the new DA" in a 2013 SVU episode would indicate that McCoy had moved on from the position presumably sometime in 2012; his replacement was unnamed. However, McCoy was the DA again as of 2018, showing up in the SVU episode "The Undiscovered Country".
Title: Jack McCoy
Content:  Law & Order: Special Victims Unit on the November 13, 2007, episode "Blinded", marked his first appearance in the Law & Order universe as district attorney. The replacement for his former position is Michael Cutter (Linus Roache), a prosecutor with a penchant for recklessness not unlike McCoy's own in his younger days. This occasionally presents political difficulties for the new district attorney. More than once, McCoy berates Cutter for reckless conduct, in the same manner as he was berated by district attorneys when he was executive assistant district attorney. In the season 19 episode "Lucky Stiff", McCoy begins his election campaign for New York County District Attorney after serving the last season and a 
Title: Jack McCoy
Content:  Entertainment Weekly television critic Ken Tucker has praised Law & Orders creator Dick Wolf for putting McCoy at the center of "some of the best episodes of the immortal series' 19th season." Tucker elaborates how the character, riding "herd over a couple of stubborn young bucks &mdash; assistant DAs Mike Cutter (Linus Roache) and Connie Rubirosa (Alana de la Garza) &mdash; McCoy argues, bellows orders, and croaks with outrage when his charges disobey his legal advice."
Title: Sam Waterston
Content:  In 1994, Waterston debuted as Executive Assistant District Attorney Jack McCoy in the fifth season of the television series Law & Order. He played the role of McCoy, who would eventually become District Attorney, through the series finale in 2010, and has reprised the role throughout the Law and Order franchise. Upon the show's cancellation, Waterston was the second longest-serving cast member (behind S. Epatha Merkerson), having reprised his role through 16 seasons. Due to the success of the New York–based TV series, Waterston and his fellow longtime Law & Order castmate Jerry Orbach were declared "Living Landmarks" by the New York Landmarks Conservancy. Waterston appeared on the 5,100th edition of Jeopardy!, on November 10, 2006, with Kathryn Erbe of Law & Order: Criminal Intent and Christopher 
Title: Law &amp; Order (season 5)
Content:  Jack McCoy (played by Sam Waterston) replaced season 4's Ben Stone (Michael Moriarty) as Executive Assistant District Attorney. Mike Logan (played by Chris Noth) departed the cast after this season, thus making Adam Schiff (played by Steven Hill) the last remaining first-season cast member.
Title: Law &amp; Order: Special Victims Unit (season 9)
Content:  Law & Order had yet to air at this point, this was the first time that Jack McCoy appeared as the DA rather than an EADA. The episode "Fight" featured guest appearances by UFC fighters Forrest Griffin and Renzo Gracie. Nicole "Coco" Austin also appeared and had a scene with her husband Ice-T. This marked their first acting appearance together even though Coco had appeared on SVU once before. Mark Valley guest starred in the following episode "Paternity" as a father who is shocked to learn that his child is not related to him. Bruce Fretts of TV Guide said he "got more dramatic meat to 
Title: Law &amp; Order (season 13)
Content:  McCoy is faced with the unlikely prospect that the defendant's attorney, his friend of 20 years and a friend of the slain lawyer, played a part in the murder of a Florida district attorney following the defendant's arrest. McCoy is able to make a deal that preserves the integrity of his adversary but not without a cost. |LineColor=6aa80f }}{{#invoke:Episode list|sublist|Law & Order (season 13) |EpisodeNumber=285 |EpisodeNumber2=8 |Title=Asterisk |DirectedBy=Steve Shill |WrittenBy=Terri Kopp |OriginalAirDate=November 27, 2002 |ProdCode=E3308 |Aux4=15.80 |ShortSummary=A star baseball player becomes the prime suspect in the murder of his limousine driver when it is discovered that the driver regularly supplied steroids 
Title: Jack McCoy
Content: Homicide: Life on the Street ; Season 6 ; Episode 5: "Baby, It's You" ; Season 7 ; Episode 15: "Sideshow" ; Law & Order: Special Victims Unit ; Season 1 ; Episode 15: "Entitled" ; Season 9 ; Episode 7: "Blinded" ; Season 11 ; Episode 21: "Torch" ; Season 19 ; Episode 13: "The Undiscovered Country" ; Law & Order: Trial by Jury ; Episode 1: "The Abominable Showman" ; Episode 8: "Skeleton" 

Question: when did jack mccoy join law and order?
Answer: 1994.