[0] It might actually be easier to change a properly written law. I hate our stupid precedent-based system in the US.
If aliens land in Germany on a field and a peasant shoots them with his shotgun, he would have committed no crime in my opinion. No murder, since Aliens are not humans. It would not be illegal hunting, since aliens are not animals. Illegal discharge of a firearm?
In the US the outcome may be very different.
English common law had many good ideas. The US criminal system may be a mess, but the underlying ideas are good. Not everybody can be Norway.... ;-)
Shooting an alien robot though, then you would have something legally problematic. Ownership? Is it so advanced it's a person? But you'd probably get something like those Star Trek episodes with legal weirdness rather than any no-crime-without-law reasoning.
You are very optimistic that they will be considered animals. For example they would have to live on organic matter. And they would have to have a spine to get more protection since living things with a spine are considered more valuable (Wirbeltiere).
GROK (And using all the Roman law principles on what German law is based):
Nullum crimen, nulla poena sine lege (Art. 103 Abs. 2 Grundgesetz + § 1 StGB) is the decisive wall that the prosecution would smash into in a real first-contact case under current German law. This principle has four sub-requirements (all must be fulfilled for a conviction):
Lex scripta – there must be a written statute → Yes, §§ 211, 212 StGB exist.
Lex certa – the statute must be sufficiently precise → “Mensch” is precise if you are Homo sapiens. It is not precise (in fact completely indeterminate) when the victim is an unknown extraterrestrial species.
Lex stricta – no punishment by analogy, no extension to the detriment of the defendant → This is the killer. → Extending the word “Mensch” in §§ 211/212 to include extraterrestrials would be a clear case of forbidden analogy that worsens the legal position of the accused. → German courts are constitutionally barred from doing this in criminal law (unlike in civil law or constitutional law, where they sometimes stretch concepts to protect victims).
Lex praevia – the law must have existed before the act → Also fulfilled, but irrelevant here.
The only difference between precedent laws and codes is that the judges act as a secondary less stable legislature.
You could very well have a mixed system where legislature has to filter and ratify court rulings to decide which become law and which do not.
In short this has nothing to do with having actual laws
GROK (And using all the Roman law principles on what German law is based):
Nullum crimen, nulla poena sine lege (Art. 103 Abs. 2 Grundgesetz + § 1 StGB) is the decisive wall that the prosecution would smash into in a real first-contact case under current German law. This principle has four sub-requirements (all must be fulfilled for a conviction):
Lex scripta – there must be a written statute → Yes, §§ 211, 212 StGB exist.
Lex certa – the statute must be sufficiently precise → “Mensch” is precise if you are Homo sapiens. It is not precise (in fact completely indeterminate) when the victim is an unknown extraterrestrial species.
Lex stricta – no punishment by analogy, no extension to the detriment of the defendant → This is the killer. → Extending the word “Mensch” in §§ 211/212 to include extraterrestrials would be a clear case of forbidden analogy that worsens the legal position of the accused. → German courts are constitutionally barred from doing this in criminal law (unlike in civil law or constitutional law, where they sometimes stretch concepts to protect victims).
Lex praevia – the law must have existed before the act → Also fulfilled, but irrelevant here.