Former Deputy U.S. Solicitor General Michael Dreeben painted a map of how some of the past year’s biggest U.S. Supreme Court decisions are teeing up issues for future terms.

Dreeben, who is among an exclusive group of lawyers who have argued more than 100 cases in front of the Supreme Court, said the past year could set the stage for a showdown on abortion rights and an expansion of the Fourth Amendment. The comments came during the American Bar Association Annual Meeting in San Francisco Friday, where he was on a panel surveying the Supreme Court’s criminal law decisions.

Dreeben recently capped off his 30-year tenure with the U.S. Solicitor General’s Office working with special counsel Robert Mueller’s investigation into Russian interference in the 2016 presidential election. Although Dreeben was silent about his time with Mueller, he had a lot to say about several Supreme Court cases that could contour the future of criminal law.

Gundy v. United States

The vote: 5-3.

The case: The justices ruled that Congress’ broad allocation of discretion to the attorney general to determine how to retroactively apply federal sex offender requirements does not violate the Constitution’s nondelegation doctrine.

The impact: In this ruling, Justice Neil Gorsuch said the executive branch can fill in the details, and apply the law when Congress has clearly enunciated a policy, delegating powers the branch already has. But Justice Elena Kagan said in the plurality ruling that the decision would be the end of government as we know it, Dreeben said. The case highlights the lack of congeniality between every branch of government.

“In a different era, before I was born, courts and legislatures used to regard their work as a partnership,” he said. “Those days are gone. Now it’s like trench warfare. If you don’t write the statute in just the right way with just the right words, you’re out of luck.” Although this creates problems for the legislature and courts, the biggest losers are citizens, he said. ”But it’s in the name of liberty, so it’s cool,” he joked. 

Gamble v. United States

The vote: 7-2.

The case: After Terance Martez Gamble was convicted for crimes involving possession of a firearm as a felon under both Alabama and federal law, the justices reaffirmed the separate sovereigns exception to the double jeopardy clause.

The impact: Dreeben said that Gamble illustrated the justices’ competing visions for what the Constitution does. The majority view was that it created a dual federalist structure of national- and state-level power by splitting the atom of sovereignty, he said. However, there just might be a hidden subtext to the ruling.

Dreeben agreed with Rory K. Little, a law professor at U.C. Hastings College of the Law in San Francisco and moderator of Friday’s panel, who said the justices had the abortion debate in mind when writing the opinion.

“It probably is a proxy war for the big battle to come in Roe v. Wade,” Dreeben said. That explains the unusual vote setting of Justices Neil Gorsuch and Ruth Bader Ginsburg both dissenting to respect historical legacy, he said. “That raises one of the most important questions of our time: Why is a judge authorized to follow a precedent that he or she thinks is an incorrect interpretation of the Constitution?” he said. “They have an oath to uphold the Constitution, not what five justices say.” 

Mitchell v. Wisconsin

The vote: 5-4.

The case: The court decided that a statute allowing law enforcement to require a blood test without a warrant from a driver who was slumped over his steering wheel did not violate the Fourth Amendment, because the act was an exigency.

The impact: Dreeben disagreed with fellow ABA panelist Mary McNamara of Swanson & McNamara in San Francisco, who said the Fourth Amendment was “limping along on its last toe.”

Dreeben regards the Fourth Amendment as an incremental piece of law. “This one was more of a continuing battle not so much a trend line that has any salience outside of this corner of the law,” he said.

In the future, Dreeben expects to see the Fourth Amendment invoked again in regard to searches of data gathered online and from tech devices, tying it in to property law. “Justices that are more on the liberal side of trying to carve out some domain of individual life protected from state use of technology to surveil,” he said. “I was on the losing side of about four of those cases. From my perspective the Fourth Amendment was coming out on top.”