The U.S. Army Criminal Investigation Laboratory uses a picture of Mickey Mouse in its official logo, and it turns out that Walt Disney is totally fine with that.
The Army's crime lab investigates serious crimes "in which the Army has an interest," providing everything from forensic laboratory support to the experts that testify in criminal cases. Since they are the folks trying to figure out what happened on a crime scene, it makes sense to have a logo that reflects the profession.
In the Army's case, that's a picture of Mickey Mouse looking like Sherlock Holmes with a magnifying glass.
From the lab's history page:
In 1943 the world was at war, and millions of Americans had been called to serve their country. The chain-of-command realized that in order to defeat the enemy aggressors, they had to control the internal criminal element. To assist in accomplishing this mission, the Army's first forensic laboratory was activated on October 1, 1943, as the Scientific Investigations Branch of the Provost Marshal's Office, 12th U.S. Army Group, Algiers, French North Africa.
The Laboratory consisted of 2nd Lt. George R. "Pappy" Bird and a photographer. They moved with advancing forces from Algiers to Naples, Italy where Sgt. James Boarders joined the new crime laboratory. The team then moved on to southern France. During this time all their work was done in borrowed offices of abandoned homes. As the offensive picked up speed, Bird, who had been promoted to captain, saw the need for a mobile laboratory. While in Marseilles, France, he obtained a weapons repair truck and its driver from the 27th MP Detachment (CI) and converted it into a laboratory. Bird later added a jeep and a chemist to his team and rejoined the allied advance; crossing the Rhine River and moving into the heart of Germany. The laboratory ended its wartime duty in Fulda, later moved to Wiesbaden, and then to Frankfurt.
The lab has been accredited since 1985, and is the only full service forensic laboratory the DoD has. On the command's website is a letter from Walt Disney Productions (which is watermarked on the logo under Mickey's feet), explaining that the studio is just fine with its appropriation of everyone's favorite mouse: