On June 8, 2009, Monserrate and Pedro Espada (D-Bronx) joined Senate Republicans in an attempted parliamentary coup for the purpose of shifting control of the Senate to the Republicans; Monserrate, Espada, and all 30 Senate Republicans voted, 32-30, to replace Senate Majority Leader Malcolm Smith with then-Senate Republican Leader Dean Skelos and install Espada as Temporary President of the Senate. This action resulted in the 2009 New York State Senate leadership crisis. A week later, Senate Democrats appointed Senator John Sampson as their leader. On the same day, Monserrate rejoined the Democratic caucus, leaving the Senate in a 31-31 deadlock. With the office of Lieutenant Governor vacant due to Eliot Spitzer's resignation, the tie could not be resolved, and the resulting legislative deadlock continued until July 9, when Espada rejoined the Democrats.