Washington ? President Barack Obama plans to nominate Solicitor General Elena Kagan to be the 112th justice of the Supreme Court, a source said late Sunday night.

Kagan, 50, the former dean of Harvard Law School, would become the fourth woman to serve on the high court; if she is confirmed, the nine-member court will have three female justices for the first time.

The choice was first reported by NBC News.

In replacing Justice John Paul Stevens, Obama would also be breaking with tradition. Every other member of the court is a former federal appeals court judge, and Kagan has never served in the judiciary. The last time a non-judge was appointed was in 1972, when President Richard M. Nixon nominated William Rehnquist and Lewis Powell in the same year.

Kagan is the government’s top appellate lawyer and representative at the Supreme Court. She was confirmed last year by the Senate in a 61 to 31 vote, and was the first woman confirmed to hold the job.

Obama considered a list of about 10 people for the job. He and Vice President Joe Biden interviewed three others, all federal appeals judges: Merrick Garland of the District of Columbia; Diane Wood of Chicago; and Sidney Thomas of Montana, who serves on the 9th Circuit in San Francisco.