ATLANTA—The evidence in his office gave the judge pause: a half-eaten apple and some very distinctive footprints.

Federal bankruptcy Judge Paul W. Bonapfel reported the break-in last week at the Richard B. Russell Federal Building in downtown Atlanta.

The intruder made no effort to cover his tracks across a stack of federal memos in the 14th-floor office. When the judge called in his staff and others to examine the scene, the evidence was conclusive: The perpetrator was a raccoon.

In the following days, judges and staff who work in the building reported other thefts—chocolate chip cookies stolen from a 10th-floor desk, a sandwich on the ninth floor, and a packet of dried soup purloined from the 23rd floor.

A court clerk created a “wanted” poster, and Bonapfel’s staff posted a “raccoon crossing” sign on the judge’s door.

Workers from a company that specializes in catching wildlife placed a trap in the ceiling over a judge’s office and baited it with tuna.

The wait ended Monday when a judicial assistant heard a noise overhead. Two workers removed the ceiling tiles and grabbed the suspect.

Office workers named the raccoon “Russell,” in honor of the building’s namesake. The General Services Administration, which manages the building, theorizes that Russell wriggled into the heating system from outside.