It is not guaranteed to be accurate or up-to-date, though we do refresh the database weekly. More limitations on accuracy are described at the GPO site.
United States Code 13 USC 301 - Collection and publication
13 USC 302 - Rules, regulations, and orders
13 USC 303 - Secretary of Treasury functions
13 USC 304 - Filing export information, delayed filings, penalties for failure to file
13 USC 305 - Penalties for unlawful export information activities
13 USC 306 - Delegation of functions
13 USC 307 - Relationship to general census law
18 USC 1692 - Foreign mail as United States mail
18 USC 1693 - Carriage of mail generally
18 USC 1694 - Carriage of matter out of mail over post routes
18 USC 1695 - Carriage of matter out of mail on vessels
18 USC 1696 - Private express for letters and packets
18 USC 1697 - Transportation of persons acting as private express
18 USC 1698 - Prompt delivery of mail from vessel
18 USC 1699 - Certification of delivery from vessel
18 USC 1700 - Desertion of mails
18 USC 1701 - Obstruction of mails generally
18 USC 1702 - Obstruction of correspondence
18 USC 1703 - Delay or destruction of mail or newspapers
18 USC 1704 - Keys or locks stolen or reproduced
18 USC 1705 - Destruction of letter boxes or mail
18 USC 1706 - Injury to mail bags
18 USC 1707 - Theft of property used by Postal Service
18 USC 1708 - Theft or receipt of stolen mail matter generally
18 USC 1709 - Theft of mail matter by officer or employee
18 USC 1710 - Theft of newspapers
18 USC 1711 - Misappropriation of postal funds
18 USC 1712 - Falsification of postal returns to increase compensation
18 USC 1713 - Issuance of money orders without payment
18 USC 1714 - Repealed.
18 USC 1715 - Firearms as nonmailable; regulations
18 USC 1716 - Injurious articles as nonmailable
18 USC 1716A - Nonmailable locksmithing devices and motor vehicle master keys
18 USC 1716B - Nonmailable plants
18 USC 1716C - Forged agricultural certifications
18 USC 1716D - Nonmailable injurious animals, plant pests, plants, and illegally taken fish, wildlife, and plants
18 USC 1716E - Tobacco products as nonmailable
18 USC 1717 - Letters and writings as nonmailable
18 USC 1718 - Repealed.
18 USC 1719 - Franking privilege
18 USC 1720 - Canceled stamps and envelopes
18 USC 1721 - Sale or pledge of stamps
18 USC 1722 - False evidence to secure second-class rate
18 USC 1723 - Avoidance of postage by using lower class matter
18 USC 1724 - Postage on mail delivered by foreign vessels
18 USC 1725 - Postage unpaid on deposited mail matter
18 USC 1726 - Postage collected unlawfully
18 USC 1727 - Repealed.
18 USC 1728 - Weight of mail increased fraudulently
18 USC 1729 - Post office conducted without authority
18 USC 1730 - Uniforms of carriers
18 USC 1731 - Vehicles falsely labeled as carriers
18 USC 1732 - Approval of bond or sureties by postmaster
18 USC 1733 - Mailing periodical publications without prepayment of postage
18 USC 1734 - Editorials and other matter as “advertisements”
18 USC 1735 - Sexually oriented advertisements
18 USC 1736 - Restrictive use of information
18 USC 1737 - Manufacturer of sexually related mail matter
38 USC 101 - Definitions
38 USC 3001 - Purposes
38 USC 3002 - Definitions
38 USC 3011 - Basic educational assistance entitlement for service on active duty
38 USC 3201 - Purpose
38 USC 3219
38 USC 3403
38 USC 3406
38 USC 3621
38 USC 3622
38 USC 3626
38 USC 3632
38 USC 3633
38 USC 401
38 USC 403
38 USC 404
38 USC 407
38 USC 408
38 USC 414
38 USC 416
38 USC 5001
39 USC 101 - Postal policy
39 USC 3001 - Nonmailable matter
39 USC 3002 - Nonmailable motor vehicle master keys
39 USC 3002a - Nonmailability of locksmithing devices
39 USC 3003 - Mail bearing a fictitious name or address
39 USC 3004 - Delivery of mail to persons not residents of the place of address
39 USC 3005 - False representations; lotteries
39 USC 3006 - Repealed.
39 USC 3007 - Detention of mail for temporary periods
39 USC 3008 - Prohibition of pandering advertisements
39 USC 3009 - Mailing of unordered merchandise
39 USC 3010 - Mailing of sexually oriented advertisements
39 USC 3011 - Judicial enforcement
39 USC 3201 - Definitions
39 USC 3202 - Penalty mail
39 USC 3203 - Endorsements on penalty covers
39 USC 3204 - Restrictions on use of penalty mail
39 USC 3205 - Accounting for penalty covers
39 USC 3206 - Reimbursement for penalty mail service
39 USC 3207 - Limit of weight of penalty mail; postage on overweight matter
39 USC 3208 - Shipment by most economical means
39 USC 3209 - Executive departments to supply information
39 USC 3210 - Franked mail transmitted by the Vice President, Members of Congress, and congressional officials
39 USC 3211 - Public documents
39 USC 3212 - Congressional Record under frank of Members of Congress
39 USC 3213 - Seeds and reports from Department of Agriculture
39 USC 3214 - Mailing privilege of former President; surviving spouse of former President
39 USC 3215 - Lending or permitting use of frank unlawful
39 USC 3216 - Reimbursement for franked mailings
39 USC 3217 - Correspondence of members of diplomatic corps and consuls of countries of Postal Union of Americas and Spain
39 USC 3218 - Franked mail for survivors of Members of Congress
39 USC 3219 - Mailgrams
39 USC 3403 - Matter for blind and other handicapped persons
39 USC 3404 - Unsealed letters sent by blind or physically handicapped persons
39 USC 3405 - Markings
39 USC 3406 - Balloting materials under the Uniformed and Overseas Citizens Absentee Voting Act
39 USC 3621 - Applicability; definitions
39 USC 3626 - Reduced rates
39 USC 3632 - Action of the Governors
39 USC 3633 - Provisions applicable to rates for competitive products
39 USC 401 - General powers of the Postal Service
39 USC 403 - General duties
39 USC 404 - Specific powers
39 USC 407 - International postal arrangements
39 USC 414 - Special postage stamps
39 USC 416 - Authority to issue semipostals
39 USC 5001 - Provisions for carrying mail
5 USC 552 - Public information; agency rules, opinions, orders, records, and proceedings
