Volker Beck
German Green Party MP Volker BeckGetty

Long-serving German Green Party MP Volker Beck has been caught in possession of illegal drug methamphetamine, or crystal meth.

Berlin prosecutors said they found 0.6 grams of an narcotic in the politician's possession on Wednesday, 2 March. Police sources told Bild that the drug was methamphetamine.

Beck has resigned his position as party spokesman for internal and religious affairs, as well as from his role as chairman of the German-Israeli Parliamentary Friendship Group.

In Germany, politicians are immune from prosecution, with prosecutors requiring special permission from the Bundestag to pursue criminal charges. This permission is generally granted.

"I have always represented a liberal drug policy," Beck said in a statement. "In regards to the charges that have been levelled against me, my lawyer in due course will give a statement to the prosecutor."

The 55-year-old is also well known in Germany as a campaigner for gay rights, and from 2002 to 2013 he was the Green's parliamentary group leader. In 2013 he was widely criticised after an article he wrote in the 1980s emerged, in which he called for the decriminalisation of paedophilia.

Crystal meth broke into the wider public sphere with the advent of the TV show Breaking Bad, which featured Bryan Cranston as a cancer-riddled high school teacher who begins producing the drug to pay for his medical bills.