WASHINGTON D.C., May 18 (CNA) .- A petition with tens of thousands of signatures was recently delivered to the president of Georgetown University in protest of a decision to honor U.S. Secretary of Health and Human Services Kathleen Sebelius with an invitation to speak at a commencement weekend ceremony.

Thomas Peters of CatholicVote.org said that the Catholics for Unity petition shows strong 'grassroots Catholic support' for the bishops' message about religious freedom.

'Religious liberty is the first freedom. It's there from the founding of America,' he told CNA. 'And Catholic institutions have a special responsibility to stand up for that freedom.'

Peters said that the petition is a 'positive protest' that allows American Catholics 'to come together for something that we all hold dear, which is the right to practice our faith fully.'

On the afternoon of May 17, Thomas Peters joined several concerned members of the Georgetown community to deliver the Catholics for Unity petition with some 35,000 signatures to the office of university president John J. DeGioia.

The petition ' which has continued to gain signatures ' is the largest of several open letters protesting Georgetown's decision to honor Sebelius.

Led by Brian Burch, president of CatholicVote.org, the signatories argued that the invitation harms the unity of the bishops' fight for religious freedom, a battle that is largely centered on the current contraception mandate.

They warned that allowing the invitation to stand will only 'inflame this conflict, invite justified protests, cause great harm and detract from the necessary dialogue required to resolve the issues surrounding this mandate.'

Georgetown has come under fire for inviting Sebelius as a featured speaker at a commencement weekend awards ceremony. She is addressing the university's Public Policy Institute awards ceremony on May 18.

Sebelius has been the center of controversy since issuing a federal mandate that will require employers to offer health insurance plans covering contraception, sterilization and abortion-inducing drugs, even if doing so violates their religious beliefs.

Catholic bishops from every diocese in the U.S. have spoken out against the mandate, warning that it poses a grave threat to religious liberty and could force Catholic hospitals, schools and charitable agencies across the nation to close down.

Sebelius also has a long history of supporting abortion, both in her current position and in her former role as governor of Kansas.

The Archdiocese of Washington, D.C. denounced the invitation, saying that Georgetown had displayed an 'apparent lack of unity with and disregard for the bishops' and all those who are fighting to defend religious liberty.

A May 10 editorial in the archdiocese newspaper called the decision 'disappointing, but not surprising.'

President DeGioia defended the invitation in a May 14 statement. He said that the university is 'committed to the free exchange of ideas' and was not attempting to endorse Sebelius' views or challenge the U.S. bishops.

However, Peters argued that there is a difference between discussing ideas in an academic setting and offering someone a public platform to speak, which is 'what we use to honor people.'

'There's no one protesting Sebelius just coming in the audience,' he explained. However, 'she doesn't have the right to be put in a place of authority and to be part of the teaching office that universities hold.'

Brendan Gottschall, a member of the class of 2012, called the invitation 'a misrepresentation of Georgetown's Catholic identity and community.'

He said that there are many Catholics on campus who do not agree with the decision to honor Sebelius.

Deirdre Lawler, who works for the university's Tocqueville Forum on the Roots of American Democracy, said the invitation 'is nothing less than a scandal and a blow to unity within the Church."

'There are no two ways to read this,' she explained. 'Georgetown University, which proudly wears the title of a Catholic institution, is bestowing an honor upon a woman who has essentially declared herself at war with the bishops and all who hold religious freedom dear.'

Lawler said that as a staff member of the university, she is 'ashamed of the institution.' Given the current situation between Sebelius' department and the Catholic Church, she does not believe that Georgetown can 'host and honor Sebelius in good conscience.'

'This invitation ought to have been rescinded in the name of fidelity to the Church, in the name of religious freedom, and in the name of Truth,' Lawler said.

'I hope that President DiGioia does take some time to flip through the many, many pages of signatures we left on his desk, just so that he understands what a huge number of people are willing to speak up in fidelity to the Church.'