[6] Fresnedi entered politics in 1986 when he was appointed as an officer-in-charge of Muntinlupa, then a municipality, following the People Power Revolution that formed a new government under President Corazon Aquino.

The tandem served three terms until 1998, three years after Muntinlupa was formally converted into a highly urbanized city and established its own legislative district in the Philippine House of Representatives for the 1998 election.

[9] In February 2015, Fresnedi presented a single-step transaction system for registering business licenses in Muntinlupa.

[7] In March 2019, a resident of Putatan filed charges of graft and plunder against Fresnedi before the Ombudsman of the Philippines for allegedly overpricing a lot in the barangay by ₱1,500 per square meter in 2014.

According to the residents, Fresnedi compelled the Muntinlupa city council to pass a resolution authorizing him to extend the contract of Linde plc and four other entities through lump sum transactions.

The Philippine Chamber of Commerce and Industry also awarded Muntinlupa the "Most Business-Friendly LGU" in 2017 and 2018, and a special citation was given in 2019.

[16] In 2019, the Philippine Department of Education reported that Muntinlupa had the highest number of scholarship beneficiaries in the country, with over 65,000 scholars.

[20] In March 2019, Fresnedi led the donation of ten fire trucks worth ₱52.3 million to nine barangays in the city.

He switched places with incumbent representative Ruffy Biazon, who is One Muntinlupa's standard bearer for mayor.