Times New Roman is available at no cost under the Microsoft Core Fonts for the Web. (Microsoft no longer distributes this, but the license allows redistribution and redistribution is popular). AFAIK, Apple explicitly licenses the fonts and most open source OS distributions have a package for these fonts.

It's not libre, but font copyright is weird anyway, and the federal government doesn't always need to follow copyright.

and the federal government doesn't always need to follow copyright

It's worth noting that most if not all works created by the government are in the public domain. There are some exceptions but PD is the default.