Twenty-three-year-old Brandon Grimes is charged with first-degree murder in the January 2007 shooting death of 34-year-old Detective Troy Chesley.

Police say Chesley was gunned down outside a home in the 4500 block of Fairfax Road in what investigators believe was a robbery attempt.

During a hearing Monday, a judge ruled that prosecutors could not present evidence connecting Grimes to a carjacking four before the homicide. Judge Timothy Doory ruled the evidence would be prejudicial.

In May, a Baltimore jury found Grimes not guilty of separate handgun charges stemming from an incident in April 2006.