The dismissals are "due to a violation of team rules and an ongoing pattern of conduct unbecoming of a representative of Seton Hall athletics," read a statement released by the school.
Lawrence -- a Newark, N.J., native who transferred from Missouri in 2008 -- had appeared in all 24 games so far this season, including seven starts. He was averaging 4.5 points, 3.1 rebounds and 2.9 assists in 24 minutes per game.
Jackson, who hails from Brooklyn, appeared in 19 games, averaging 4.6 points and 1.2 rebounds in 14.7 minutes per game.
Lawrence has been in trouble before. In November 2009, he was charged with driving under the influence and driving with a suspended license after he was involved in a two-car accident because he was driving on the wrong side of the Garden State Parkway. He received five years' probation for the incident.
Seton Hall suspended Lawrence for the first eight games of the 2009-10 season, following the accident and charges.
The dismissals brought back memories of last season when the
Pirates' program was riddled with problems on and off the court
that led to the firing of coach Bobby Gonzalez despite a 19-win
That season ended with forward Herb Pope being was ejected from
an NIT game for hitting a Texas Tech player below the belt, and
Gonzalez picking up his seventh technical foul of the season.
When Kevin Willard was hired as coach less than two weeks later, the school
said it had expectations as to how coaches and players would
Seton Hall (11-14, 5-8 in Big East) defeated Rutgers 69-64 Saturday night.
Information from The Associated Press contributed to this report.