The "laws of science" are a human construct when the phrase refers to scientific procedure.

They are not a human construct when - as is frequent - the phrase is used as a loose synonym for "the laws of nature." This may be popular, not technical, usage, but it's so common that it can't be ignored.

For a contrasting example: because the word "physics" commonly applies to both the study and the phenomena, a phrase like "the laws of physics" applies equally to human constructs and natural phenomena.