[3] He served in the German Army as a First Lieutenant Artillery Officer during World War I but was injured during a battle at the Italian front.
He first started a practice in Maine but subsequently moved to Yorkville, New York City due to the large community of German-Americans in that area of Manhattan.
[1] In 1938, about 13 years after Griebl's emigration to the United States, FBI Special Agent Leon G. Turrou ran an investigation that targeted Nazi German spies actively working within the country.
Griebl agreed to the meeting in hopes of obtaining the release of his wife, who was then under bail in New York in connection with the espionage trial of individuals indicted as part of the spy ring.
Griebl remained a fugitive until March 14, 1950, when a nolle prosequi order (dropping the case against the defendant) was approved on the recommendation of U.S. Attorney Irving H. Saypol.