WASHINGTON — Justice Elena Kagan says the longer the Supreme Court is stuck with only eight members, the more it has to deal with the prospect of not being able to decide cases.

Kagan said in an appearance at Harvard Law School that the court has decided some cases only by narrowing the issue so much that it left undecided the real reason the court took up the dispute in the first place.

“Over time, that’s a problem,” she said.

The law school made a video of her Sept. 8 comments available on Friday.

The high court has been short a member since Justice Antonin Scalia died in February. President Barack Obama has nominated federal appeals court Judge Merrick Garland as a replacement, but Senate Republicans have refused to hold a hearing or a vote during Obama’s last year in office.

Kagan gave credit to Chief Justice John Roberts for working to forge compromise on the court, now evenly split with four liberal and four conservative members. She said the justices would continue to find ways to resolve cases.

“But is that cost-free? No, it’s absolutely not,” she said.

Four cases ended in a tie after Scalia’s death. That means the lower court decision remains in place without setting a nationwide precedent.

“A tie does nobody any good,” Kagan said. “Presumably we’re there for a reason. We’re there to resolve cases that need deciding, answer hotly contested issues that need resolving, and you can’t do that with a tie vote.”