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It depends on the scope of the livescan.
(All that a "Livescan" does is capture an image of the fingerprints, what the relevant issue as far as "how far back" is concerned, is what type of report or investigation is being done).
This link here: https://oag.ca.gov/fingerprints will provide you with a much more detailed response regarding what is provided following a background request.
The biggest distinction is one that is a "DOJ" (California State) and an "FBI" report.
Your DOJ report generally will only report convictions as an adult that have not been expunged.
Your FBI report will show any arrests (regardless of the disposition).