Pocket Part System in the United States

Pg. 6-15 of the book “In Legal Research, How to Find & Understand the Law”, by Stephen Elias and Susan Levinkind, provides a good overview of the Pocket Part System:

“Federal statutes often are amended or replaced by
subsequent sessions of Congress. Indeed, many laws are
totally changed by amendment and deletion in just a few
years. This continuous change has required a method for
keeping hardcover federal annotated codes up-to-date.
The primary method for doing this, in virtually universal
use for all collections of annotated statutes, both state and
federal, is called the “pocket part system.”

Pocket parts are paper supplements that fit inside each
hardcover volume, usually at the back. They are published
once a year and contain any statutory changes occurring in
the interim. When the pocket parts get too bulky because
of legislative changes, either a new hardcover volume is
published that incorporates all of the changes since the last
hardcover volume was published, or a separate paperback
volume is published that sits on the shelf next to the hardcover
book.

Always check the pocket part to see if a statute you’re
reading has been amended or repealed. If you don’t, you
may find that the statute you discovered in the hardcover
volume has long since been amended or even repealed.

If the book you are using does not have a pocket
part or a separate paperback pamphlet next to the
hardcover volume on the bookshelf, and the book was not
published in the year you are doing your research, inform
the law librarian and ask if there is a current pocket part
available. Never rely on out-of-date codes when doing
statutory research unless you know that the statute being
sought has not been amended since the publication of the
book.

The pocket parts for U.S.C.A. reprint the sections of any
statutes in the hardcover version that have been amended.

Sections of the statute that have not been amended are not
reproduced in the pocket part; instead, you are referred to
the hardcover volume for the text. The example set out
below first shows the portion of the statute as found in the
hardcover volume and then shows how amendments
appear in the pocket part. Note how the pocket part refers
the reader back to the hardcover volume for sections that
have not been changed.

The United States Code Service (U.S.C.S.) handles its
pocket part in exactly the same way.

When you know the approximate date a statute was
passed, you should first check the publication date
of the hardcover volume. If this date is prior to your statute,
then go right to the pocket part. In fact, many researchers
prefer to start with the pocket part and then work backwards
to the hardcover. Either way is fine so long as you never,
ever, forget to check the pocket part.

Pocket parts are published only once a year.”

Pocket Part to the Pocket Part

In pages 6/17 and 6/18 of the above book:

“Each federal code has a periodic advance legislative service
that prints statutes a month or two after they have been
passed by Congress. The one for U.S.C.A. is called the
U.S.C.A. Quarterly Supplement; the one for U.S.C.S. is the
U.S.C.S. Advance Legislative Service.

These advance services are, in one sense, a pocket part to
the pocket part and make it possible to find a federal
statute shortly after it becomes law. The new or newly
amended statutes are organized in these services by public
law number. As explained in Section B, above, this is the
number the statute carries when it emerges from Congress.

If you don’t know the public law number, you can use the
subject index in either of the supplements. For example, if
you are looking for a new statute concerning conservation,
look under “conservation” in the index to determine the
page on which the new statute is located.”