Published: Apr 05, 2010 10:38 AM EDT

LOS ANGELES (AP) — Dozens of Michael Jackson fans are rallying outside a Los Angeles courthouse where the pop star's doctor has a hearing in his involuntary manslaughter case.

The fans, singing "We are the World," wore T-shirts emblazoned with Jackson's picture and the slogan, "Justice for Michael." They also carried placards demanding stronger charges against Dr. Conrad Murray in Jackson's death.

Some fans say they came from as far as the Netherlands and France and brought a huge banner signed by fan club members in Europe. They say they remain devoted to Jackson's musical legacy and will not be satisfied unless Murray goes to prison. If convicted, Murray could face a maximum of four years behind bars.

The court agenda Monday included assigning a judge for the case.