Update: Supreme Court justices press gay rights lawyer early in highly anticipated marriage arguments

DETROIT, MI -- The Supreme Court justice seen by many as the deciding vote in the nation's same-sex marriage debate made early comments during highly anticipated oral arguments Tuesday could cause worry among gay rights activists.

Justice Anthony Kennedy said that marriage has been understood as the union of one man and one woman for "millennia-plus time," according to an Associated Press reporter in the courtroom.

"It's very difficult for the court to say 'We know better,'" Kennedy said during gay rights lawyer Mary Bonauto's presentation of arguments.

The hearing was interrupted at one point by a protester.

Five lawyers are expected to spend more than two hours presenting arguments.

Full audio from the session is expected to be released later this afternoon.

The court is considering two specific questions.

The first in relation to cases out of Michigan and Kentucky:

"Does the 14th Amendment (equal protection) require a state to license a marriage between two people of the same sex?"

And the second on gay marriage cases out of Tennessee and Ohio:

"Does the 14th Amendment require a state to recognize a marriage between two people of the same sex when their marriage was lawfully licensed and performed out of state?"

Michigan's case stems from a 2012 lawsuit filed by a Hazel Park lesbian couple who can't jointly adopt their four children without a legal marriage.

April DeBoer and Jayne Rowse were in Washington for the arguments Tuesday.

U.S. Rep. Debbie Dingell (D-Dearborn) planned to host a reception for the couple after the hearings.

Legal experts supporting the coupled planned to speak to reporters at 4 p.m.

Many will be listening for clues from Kennedy and Chief Justice John Roberts to gauge the direction of a ruling expected in June or July.