Lacwasan was elevated as Governor of Mountain Province following the death of Leonard Mayaen on March 31, 2016. As the vice governor at the time of Mayaen's death, Lacwasan was sworn in on April 5, 2016, after a period of mourning as per Igorot customs. He served Mayaen's unexpired term until June 30, 2016.[1]
Lacwasan was supposed to seek a reelection bid as vice governor for the 2016 elections. The deceased Mayaen, who ran as an independent candidate, was the sole candidate for governor for that election. Lawyer and daughter of Mayaen, Kathy Jyll Mayaen-Luis claimed to be rightful governor as a substitute for her father's candidacy. However, her claim was disputed due to a rule that no substitution is allowed for an independent candidate. Lacwasan would be ordered by the Commission on Elections to serve as acting governor once again.[2]