From 1908 to 1911 he studied law at the Universities of Freiburg, Munich and Bonn. In 1911 he graduated from the 1st state exam and then was a trainee at the local courts and Merzig Saarlouis, the District Court and the Prosecutor's Office and the Saarbrücken Higher Regional Court of
Cologne. In 1921 he passed the 2nd state examination and was then until 1934 Attorney in Saarbrücken. From 1934 until 1935 he was head of the
Gestapo in
Trier, after being recommended by
Hermann Goring. From 1935 to 1936 he acted as a representative of Germany at the Supreme Court vote in Saarland, which was to monitor the referendum on the membership of the Saarland. Then he served until 1945 as Chief Prosecutor at the Higher Regional Court in
Zweibrücken. During this period he was also 1938-1940 Special Representative with the authority of the Reich Commissioner for the reunion of
Austria with the German Reich and from 1940 to 1945 head of the German justice administration in occupied
Lorraine. Even after the war Welsch took numerous functions: From 1948 to 1957 he was president of the National Insurance Office and the country's supply Court of Saarland and 1950 Chairman of the Board of the Railways of the Saarland. ==Political offices==