Dive Brief:

• When California's Fair Pay Act goes into effect on January 1, 2016, it has some aspects that go beyond the scope of similar equal-pay laws in the U.S., according to Fortune.
• James McDonald, a managing partner in employment law at the Irvine, Calif. office of Fisher & Phillips, told Fortune that it's the "the most aggressive equal pay law in the nation." 
• McDonald explained that rather than equal pay for men and women doing equal work, the new law calls for pay equity among employees whose jobs are "substantially similar," which means employees no longer have to prove they're paid less than someone else doing an exactly identical job, which he adds "provides a rather easy standard for employees to satisfy" to file a suit or a complaint with state regulators.

Dive Insight:

McDonald told Fortune that the new law also makes it harder for employers to justify unequal pay, which employers can currently do in certain cases, including a formal union-style seniority system or a sales commission program.

Employers outside of California are also affected, McDonald noted, because it applies in any location where a California employer does business, though that has not yet been clearly defined.

For HR, that will likely mean paying closer attention to granular details of jobs and who does what and how people are paid. Also, McDonald told Fortune that California's new law could be the prototype for other state legislatures looking to enact equal pay laws.