In Carroll's first national televised appearance, against Indiana, he scored 12 points, had 6 rebounds and 3 blocks in 20 minutes coming off the bench in an 86–76 win.

With senior Walter Jordan, he helped lead the team to a 16–11 record and a fourth-place finish in conference play.

Playing with a slowed down, controlled system compared to Schaus' fast-pace style, Carroll and senior point guard Jerry Sichting led Purdue to a first place Big Ten tie with an Earvin Johnson-led Michigan State.

Not receiving the favor of the two teams to advance to the NCAA Tournament, Carroll led Purdue to the NIT Finals his junior year, losing to in-state rivals, Indiana.

[3] Golden State's decision to part with two future hall-of-famers, who would both go on to win multiple NBA Finals with Boston, would affect public perception of Carroll throughout his career.

Carroll helped lead the team past the Jazz and to the Western Conference Semifinals, where despite him averaging 20 points, 4.8 rebounds and 1.6 blocks,[11] Golden State lost to the eventual champion Los Angeles Lakers.

In December 1987, he was traded with Sleepy Floyd to the Houston Rockets for Ralph Sampson and Steve Harris to play under head coach Bill Fitch.

Carroll was traded to the New Jersey Nets for the 1988–89 season alongside Lester Conner for Tony Brown, Lorenzo Romar, Tim McCormick and Frank Johnson.

He was traded in the middle of the 1989–90 season to the Denver Nuggets for Michael Cutright on February 21, 1990, where he averaged 10 points a game and appeared in the first round of the 1990 NBA Playoffs, losing to the San Antonio Spurs.

At the age of 26, Carroll established the BroadView Foundation to financially support and participate in organizations and programs that serve lower socio-economic groups and individuals in communities of color.

In addition to establishing college scholarships, Carroll and BroadView have funded afterschool programs, elder care, Aid to Children of Imprisoned Mothers, True Colors Theatre, Task Force for the Homeless, and Georgia Innocence Project.

[1] In 2013, Carroll expanded his support of the Georgia Innocence Project by fully funding the salary for a full-time staff position.

All proceeds from Joe Barry Carroll Publishing are donated to selected nonprofit entities including the Georgia Innocence Project.

[16] The book has received praise from Tony Award winning Broadway stage, Television and Film Director Kenny Leon; Emory University Associate Professor of Art History and African American Studies, Michael D. Harris; Atlanta Daily World Publisher, M. Alexis Scott; and WABE/NPR Director of Arts and Cultural Programming, Lois Reitzes.

[17] In 2014 Carroll received the Hank Aaron Champion for Justice award from the Atlanta Braves and the National Center for Civil and Human Rights in recognition of his ongoing philanthropy and activism.