Are they a form of statute that get periodic parliamentary passage/assent? Or a form of secondary legislation? Or is the root of their forcefulness more in the authority of the courts under common law?
1I posted my answer referencing the Criminal PRs, before before noticing you asked about the Civil PRs. But they're basically follow the same processes with different primary legislation. I'll dig around and add Civil links in due course– RickAug 9, 2022 at 17:13
At the time of writing, there 642 various UK Procedure Rules and amendments. These are all secondary legislation (discussed here).
Taking the Criminal Procedure Rules 2020 as an example, these Rules are made under primary legislation found at section 69 of the Courts Act 2003:
69 Criminal Procedure Rules
(1)There are to be rules of court (to be called “Criminal Procedure Rules”) governing the practice and procedure to be followed in the criminal courts.
(2)Criminal Procedure Rules are to be made by a committee known as the Criminal Procedure Rule Committee.
(3)The power to make Criminal Procedure Rules includes power to make different provision for different cases or different areas, including different provision—
(a)for a specified court or description of courts, or
(b)for specified descriptions of proceedings or a specified jurisdiction.
(4)Any power to make Criminal Procedure Rules is to be exercised with a view to securing that—
(a)the criminal justice system is accessible, fair and efficient, and
(b)the rules are both simple and simply expressed
I think this answer would be completely correct and identical in essence if only the references to criminal procedure were modified to refer to civil procedure, so I'm accepting it on that basis. Aug 9, 2022 at 18:14