Obstructionist n. : One who hinders progress; one who obstructs business, as in a legislative body.

Obstructionist a. : Of or pertaining to obstructionists.

Example:
Why are the Obstructionist republicans working to undermine the presidents economic policies?

Taxonomy
Obstructionism, tactic, slow walking, free encyclopedia, Movement, Reform, 1870-1914, E. Collins, Educational Company, Edco, Obstruction of justice, search, interference, legislation, parliamentary procedures, obstructionists, filibuster, proposal.

Defination from the web:
... Another famous obstructionist is Jesse Helms. [edit] See also. Quorum Busting. Disappearing quorum. Passive-aggressive behavior. Abstentionism [edit] References ...