[3][4] He was sworn into office as secretary of state on January 2, 2009, by Chief Justice Federico Hernández Denton, fulfilling the role of lieutenant governor (first-in-line of succession) in the islands.

[5][6] He was appointed by Governor Pedro Pierluisi as a member of the Civil Rights Commission (Puerto Rico) on February 8, 2024, a nomination pending Senate confirmation.

In 1984, the Jaycees honored him with the Outstanding Young Man of the Year in Journalism Award for his weekly columns in the now-defunct El Mundo daily newspaper.

The report on the conditions of the companies availed to the tax benefits of the now-defunct Section 936 of the Federal Internal Revenue Code earned him an interview in ABC's Prime Time Live program and Univision Network.

In 1996, along with Fortuño, he was appointed by Governor Pedro Rosselló as co-chair of the NPP's Platform Committee, a position to which he was reappointed by the party's 2000 gubernatorial candidate Carlos I. Pesquera.

In 2008, along with Roberto Prats, he co-chaired Sen. Clinton's successful campaign for Puerto Rico's presidential primary, which she won 68% to 32%, the second highest vote margin (after West Virginia) in that year's election cycle.

He participated in the multilateral negotiations between the governor, the Speaker, McClintock, the Roman Catholic Archbishop of San Juan, the Episcopal bishop for the Diocese of Puerto Rico and several Protestant leaders, in breaking the logjam that led to the end of a two-week-long government shutdown in May 2006.

This sanction was endorsed in a Party state assembly in 2005, for allegedly insulting high officials of the NPP (including its president, Pedro Rosselló), rejecting to comply with majority decisions of the party's state assembly (including support for Rossello's Senate presidency bid), and allegedly making political alliances with the PDP delegation in the Senate.

The two were the decisive votes to pass a Concurrent Resolution proposing a constitutional amendment that would turn Puerto Rico's bicameral legislature in a unicameral system, an issue not addressed by the party's platform.

Members of the NPP hardcore rank and file had clearly stated they would never forgive the negotiations they allege took place against the statehood movement by McClintock, and did not acknowledge the Senate President's extensive efforts to lobby in Congress and generate national media coverage for the enactment of legislation to provide self-determination for Puerto Rico, as proposed by President George W. Bush's White House Task Force on Puerto Rico's Political Status.

That "reasonable time" ended on March 29, 2007, when he, along with four other senators, filed suit in San Juan Superior Court, claiming that NPP leaders violated the due process required by the state elections laws when parties attempt to discipline its members.

Judge Oscar Davila Suliveres ruled on April 12 against NPP Secretary Thomas Rivera Schatz and determined the lawsuit was meritorious and would be decided on the merits within several days.

All sanctions against the McClintock Six were nullified by San Juan Superior Court Judge Oscar Dávila Suliveres on May 8, 2007, who determined that they had broken no programmatic or rule-based accord, and that they were free to run in the NPP's 2008 primary.

A 2007 El Nuevo Día opinion poll reflected that, in spite of being censured by the New Progressive Party, he had become its third most popular leader, after Resident Commissioner Luis Fortuño and party president Pedro Rosselló, surpassing San Juan Mayor Jorge Santini, former gubernatorial candidate Carlos Pesquera and Bayamón Mayor Ramón Luis Rivera.

Zak Hernández, bolstered by the approval by 25 of the 27 members of the Senate of Puerto Rico of a resolution he authored expressing the legislative body's "profound preoccupation with the Panamanian leader's election.

In 2007, McClintock convened a meeting in Honolulu, Hawaii, of Senate presidents from Alaska, Hawaii, Guam, the Northern Marianas Islands and Puerto Rico to establish the Outlying Areas Senate Presidents Caucus to discuss issues common to the nation's outlying areas and devise common strategies to deal with such issues.

One outcome of his efforts was Federal Communications Commission chairman Kevin Martin's support of the XM/Sirius satellite radio merger after Sirius committed to extending service to Puerto Rico.

McClintock's presidency began to draw to a close when on June 30, 2008, he gaveled the Senate out of the seventh and last regular session of the term.

[5] Due to the fact that the appointment entailed serving the role of lieutenant governor, McClintock required confirmation by both the Senate of Puerto Rico as well as the House of Representatives.

Having been confirmed, he was sworn in on January 17, 2009, by Bayamón Superior Court Judge Angel Manuel Candelas in a private ceremony in the neighborhood where McClintock was raised and lived for many years.

[27] In 2011, he was the keynote speaker at Hispanic Heritage activities in Cleveland, Ohio[28] While Secretary of State, McClintock met Republic of China President Ma Ying-jeou.

He subsequently met with Preval in San Juan and was appointed by Secretary Hillary Clinton as part of the United States delegation to a meeting in Martinique in March 2010 to plan the multi-nation redevelopment of Haiti.

In July, 2011, he was selected as co-chair of the National Association of Secretaries of State's International Relations Committee at its 2011 summer meeting in Daniels, West Virginia.

Due to the temporary closure of the Roberto Sánchez Vilella Government Center's North Tower by the EPA in 2012, the ribbon-cutting ceremony was pushed back beyond McClintock's incumbency as secretary of state.

Secretary McClintock visited eleven countries, including being a member of United States delegations, traveling to coordinate disaster relief, represent Gov.

During his term as secretary of state and previously during his service in the Senate, McClintock met with numerous religious leaders, including the Papal Nuncio in the Dominican Republic, who has ecclesiastical authority over the Roman Catholic Church in Puerto Rico, the Presiding Bishop of the Episcopal Church Katharine Jefferts Schori and the chief abbot of the Buddhist Shaolin Temple in Henan, Shi Yongxin.

Prior to serving as secretary of state, his official foreign travels in four continents, which set the stage for his level of international activity, included:

The government of Spain financed a World Bank pre-feasibility study on the possible interconnection of Puerto Rico and the Dominican Republic's power systems, which would be an integral part of the proposed Caribbean Energy Grid.

On January 2, 2013, following long-standing tradition, he opened the Governor-elect's Inaugural Ceremony, minutes before completing this last stage of his public service career.

[61] For over a quarter century McClintock has been a member of the board of directors of TWC, a non-profit based in Washington, D.C.[62] In 2010 he was the keynote speaker at the Universidad del Este commencement in Puerto Rico.