Archbishop Wilton Gregory installed as new archbishop of Washington, DC

Archbishop Wilton Gregory has been installed as the new archbishop of Washington, D.C. in a special mass at the Basilica of the National Shrine in the nation's capital Tuesday.

Dozens of cardinals and bishops, hundreds of priests and thousands of people attended the ceremony.

Gregory, 71, who was most recently the archbishop of Atlanta, is a moderate and the first African American to lead the Washington archdiocese. He replaces Cardinal Donald Wuerl, who resigned last year after a Pennsylvania grand jury accused him of covering up clergy sex abuse.

Gregory headed the U.S. bishops conference when it adopted a "zero-tolerance" abuse policy in 2002 to respond to the first wave of the scandal. He ran the Atlanta archdiocese starting in 2005 and is seen as a pastor very much in line with Francis' progressive vision of the church.

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While relatively small, the Washington archdiocese has always punched above its weight given its location in the nation's capital. Its archbishops traditionally are made cardinals, meaning Gregory could become the first African American cardinal.

The archdiocese, though, has become embroiled in the abuse crisis since its previous two leaders -- Wuerl and Theodore McCarrick -- were implicated in the scandal.

Francis in February defrocked McCarrick after a Vatican-backed investigation concluded he sexually abused minors and adults over his long career. It was the first time a cardinal had been dismissed from the priesthood for abuse.

Francis reluctantly accepted Wuerl's resignation in October after he lost the trust of his priests and parishioners in the months following the release of the Pennsylvania grand jury report. The report accused Wuerl of helping to protect some child-molesting priests while he was bishop of Pittsburgh from 1988 to 2006. Simultaneously, Wuerl faced widespread skepticism over his insistence that he knew nothing about McCarrick's misconduct, which was an open secret in U.S. and Vatican circles.

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Gregory has responded by expressing his own anger, shame and disillusionment at the failures of the hierarchy. In an August statement after McCarrick resigned as a cardinal, he acknowledged his own respect for McCarrick had been "clearly misplaced."

Gregory is credited for his leadership of the U.S. church during a moment of crisis, when as president of the U.S. bishops conference he persuaded church leaders to adopt toughened penalties for abusers in 2002.

Gregory is the seventh archbishop of Washington, serving a community of around 659,000 Roman Catholics.

In Atlanta, Gregory was embroiled briefly in a scandal of his own in 2014 after the archdiocese used $2.2 million in donations to buy and renovate a swank new home for the archbishop. The mansion was later sold, and Gregory apologized following an outcry from parishioners.

A native of Chicago, Gregory is a protege of the late Chicago Cardinal Joseph Bernardin, who consecrated him as a bishop in 1983. Gregory was bishop of Belleville, Illinois, from 1994 until his installation in Atlanta in 2005.

The Associated Press contributed to this report.