<P> The ability to block a measure through extended debate was an inadvertent side effect of an 1806 rule change , and was infrequently used during much of the 19th and 20th centuries . In 1970 , the Senate adopted a `` two - track '' procedure to prevent filibusters from stopping all other Senate business . The minority then felt politically safer in threatening filibusters more regularly , which became normalized over time to the point that 60 votes are now required to end debate on nearly every controversial legislative item . As a result , the modern `` filibuster '' rarely manifests as an extended floor debate . Instead , `` the contemporary Senate has morphed into a 60 - vote institution -- the new normal for approving measures or matters -- a fundamental transformation from earlier years . '' This effective supermajority requirement has had very significant policy and political impacts on Congress and the other branches of government . </P>
<P> The ability to block a measure through extended debate was an inadvertent side effect of an 1806 rule change , and was infrequently used during much of the 19th and 20th centuries . In 1970 , the Senate adopted a `` two - track '' procedure to prevent filibusters from stopping all other Senate business . The minority then felt politically safer in threatening filibusters more regularly , which became normalized over time to the point that 60 votes are now required to end debate on nearly every controversial legislative item . As a result , the modern `` filibuster '' rarely manifests as an extended floor debate . Instead , `` the contemporary Senate has morphed into a 60 - vote institution -- the new normal for approving measures or matters -- a fundamental transformation from earlier years . '' This effective supermajority requirement has had very significant policy and political impacts on Congress and the other branches of government . </P>
when did the filibuster start in the us senate
when did the filibuster start in the us senate
1806
1806