Attorney General Eric Holder's trip to Ferguson, Missouri, Wednesday brings the full weight of the U.S. government to its investigation of the police shooting of unarmed 18-year-old Michael Brown. Holder arrived in St. Louis shortly before 11 a.m. Wednesday.

Holder is expected to head to nearby Ferguson with several Justice Department officials, including members of its Civil Rights division. He will meet with the FBI and other officials carrying out an independent federal investigation into Brown's death.

A small group of protesters on Wednesday also gathered outside the building where a grand jury could begin hearing evidence to determine whether the police officer should be charged in Brown's death.

Holder has promised a thorough federal investigation. He is uniquely suited to the task of reassuring protesters that the case will be handled fairly. The first African-American to serve as attorney general, he's pushed the government into bolder action on civil rights. He's championed reduced sentences for non-violent drug crimes, opposed voting restrictions and cracked down on brutality and racial bias by police.

Holder says he knows from personal experience as a young man what it's like to be stopped and searched by police without cause. And he says the Trayvon Martin case prompted him to warn his teenage son how to act if that happens to him.