Starfleet had The Prime Directive which said that they should not interfere with the natural progression of a species. It was a conservative idea but it was often ignored by Starfleet officers for moral reasons. There was also a Temporal Prime Directive which said that when going into the past (by various means) they should not try to alter the course of history. When someone from Starfleet (or not from starfleet) violated the directive officers were justified in working to stop, them as long as they did not violate the directive themselves.
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Starfleet had The Prime Directive which said that they should not interfere with the natural progression of a species. The directive sometimes clashed with morality or common sense and on many occasions was ignored by Starfleet officers. There was also a Temporal Prime Directive which said that when going into the past (by various means) they should not try to alter the course of history. When someone from Starfleet (or elsewhere) violated the directive officers were justified in working to stop them as long as they did not violate the directive themselves.