WASHINGTON — The Supreme Court last month agreed to add another 30 minutes to the arguments over President Barack Obama’s health care reform law.

The sessions, which will be held over three days later this month (March 26 through March 28), will now span six hours.

The 30 additional minutes will be added to the original 60 minutes that was to be devoted to discussion of the effect a federal law intended to make tax collections run smoothly will have on the health care case.

That law forces people who want to challenge taxes to pay them first.

The federal government, 26 states and a small-business group jointly requested that the court spend the additional time considering whether the tax law would prevent it from ruling on the constitutionality of the law until at least 2015.

Supreme Court watchers say that the tax law — formally known as the Anti-Injunction Act — is a pivotal issue because if the court finds that the law applies to the health care legislation, the justices would likely throw out the case against the so-called individual mandate that is at the heart of the legal challenges to the law.

Anyone who wanted to sue would then have to wait to file a lawsuit until after they file their taxes in April 2015.

Besides the 90-minute discussion on the tax law’s implications on health care reform, the court will hear two hours of argument on the law’s requirement that most people purchase insurance or pay a penalty beginning in 2014; 90 minutes on whether the rest of the law can remain in place if the individual insurance requirement falls; and an hour on the expansion of Medicaid programs.

The health care reform law — formally known as the Patient Protection and Affordable Care Act — was signed into law March 23, 2010. The law is being phased in over four years.

Data released last month by the Health and Human Services Department (HHS) suggests that the parts of the law that have already gone into effect are helping to provide care to more people across the country.

HHS says that health care reform trimmed $2.1 billion from the out-of-pocket costs of nearly 3.6 million Medicare patients last year and is expected to lead to even greater savings going forward.

According to a report issued by the department, the average person with Medicare will save nearly $4,200 by 2021 because of the new law.

“The Affordable Care Act is already saving money for millions of Americans with Medicare,” HHS Secretary Kathleen Sebelius says. “As we move forward, we will close the donut hole completely and save even more money for everyone with Medicare.”

In addition, HHS says that the health care reform law provided about 54 million people with private insurance and 32.5 million people on Medicare at least one new free preventive service last year.

“Americans of all ages can now get the preventive services they need, like mammograms and the new Annual Wellness Visit, free of charge, as a result of the new health care law,” Sebelius says. “With more people taking advantage of these benefits, more lives can be saved, and costly, and often burdensome, diseases can be prevented or caught earlier.”

While proponents of the law say the savings and additional services HHS cites are a positive step toward driving down the nation’s health care costs, polls show that the country is almost evenly divided over whether the Affordable Care Act should be allowed to go forward.