Cleaves is best remembered for his career with the Michigan State University Spartans (MSU).
He was a heavily recruited high school athlete. His recruiting trip with the Michigan Wolverines men's basketball team touched off a major scandal after he was a passenger in a rollover accident. Cleaves eventually agreed to attend Michigan State University, the University of Michigan's in-state rival. He is one of the four MSU players from Flint, Michigan dubbed "The Flintstones."
Cleaves, a three-time Michigan State captain, led the Spartans to the 2000 national championship, and was named Most Outstanding Player of the Final Four.
The school's only three-time All-American, Cleaves was named Big Ten Player of the Year twice. He led MSU and the conference in career assists with 816, and is Michigan State's all-time steals leader (193). In his final home game on senior night in East Lansing, Cleaves dished out 20 assists, breaking the Big Ten single-game and career assist marks.
On February 3, 2007, Cleaves became the eighth MSU player to have his number retired.
In 2000, Cleaves was drafted by the Detroit Pistons with the fourteenth pick. During his rookie season, he played in 78 games, averaging 5.4 points and 2.7 assists.
Cleaves was traded to the Sacramento Kings shortly before the 2001–02 season for Jon Barry and a first-round draft pick. After two seasons playing sparingly, he signed as a free agent with the Boston Celtics, but was waived before 2003–04's regular season began. He played with the Cleveland Cavaliers in four games. He was then signed by the Seattle SuperSonics, was cut during 2004–05, and re-signed during the following campaign.
Following his NBA stint, Cleaves appeared for the Fayetteville Patriots and the Bakersfield Jam of the D-League, also playing abroad with Russia's Unics Kazan and Greece's Panionios BC. In 2008, he played with the Denver Nuggets in their pre-season, but was waived before the October 29 tip-off.
On March 14, 2010, it was announced that Cleaves had joined Fox Sports Detroit as a Detroit Pistons studio analyst. In addition Cleaves has branched out into music as an owner of the record label All Varsity Entertainment, featuring Jon Connor.
In October 2015, Cleaves was investigated for his role in an alleged sexual assault. Cleaves is accused of taking a 24-year-old woman to a motel in Mundy Township, on September 15, 2015, keeping her against her will and sexually assaulting her. On March 16, 2016, Cleaves was charged with unlawful imprisonment, assault with intent to commit criminal sexual penetration, second-degree criminal sexual conduct and two counts of third-degree criminal sexual conduct. He was released on a $150,000 personal bond. He was originally scheduled to have a probable cause hearing on March 29, and a preliminary examination on April 5, both before Judge M. Cathy Dowd. However, the case was delayed three weeks, as lawyers need more time to review evidence, and was rescheduled to April 19. The case is being handled by Wayne County because Genesee County Prosecutor David Leyton had a conflict of interest.
On December 5, 2016, all charges against Cleaves were dismissed. Prosecutors promptly appealed. On April 10, 2017, Genesee Circuit Court Judge Archie L. Hayman ruled that District Court Judge M. Cathy Dowd abused her discretion in finding no probable cause that Cleaves committed a crime, remanding the case to district court and ordering it bound over for a jury trial. On May 16, 2017, Cleaves' attorneys appealed the decision to the Michigan Court of Appeals, arguing that Judge Hayman "ignored the evidence of the case".