Miller Act
A federal law requiring payment and performance bonds on most federal construction contracts over a set dollar threshold, protecting the government through the performance bond and protecting subcontractors and suppliers, who can't file a mechanic's lien against federal property, through the payment bond instead.
Why it matters
A mechanic's lien simply doesn't work as a remedy on federal property, so the Miller Act's payment bond isn't an extra protection layered on top of lien rights, it's the only real remedy a federal-project subcontractor has if it goes unpaid.
On a real project
A subcontractor on a federal courthouse project goes unpaid by the general contractor and, unable to file a lien against government-owned property, files a claim against the project's Miller Act payment bond instead to recover what it's owed.
Who this matters most to
A Surety Bond Underwriter prices and issues the payment and performance bonds the Miller Act requires before a contractor can even be awarded a qualifying federal contract.
Where this goes wrong
A subcontractor on a federal project goes unpaid and tries to file a mechanic's lien against the government-owned property, not realizing liens don't attach to federal property at all. The Miller Act's payment bond, not a lien, is the actual remedy, and missing that bond claim's own notice deadline can forfeit the remedy too.