Conversation so far:
what was the trial about?
In February 1992, Mielke was put on trial for the first degree murders.
who was he accused of murdering?
Captains Anlauf and Lenck as well as the attempted murder of Senior Sergeant Willig.
what was the motive behind the killings?
CANNOTANSWER.
how long was the trial?
twenty months.
what was the verdict?
Erich Mielke was convicted on two counts of murder and one of attempted murder.

Question: how long was he sentenced to?
Self-contained rewrite: how long was Erich Mielke sentenced to?