According to the American Council on Education's academic costume code, academics must fasten a long tassel to the middle point of the top of the mortarboard cap. Although the code stipulates that the tassel lie in whatever position it falls, many colleges utilize the position of the tassel during commencement ceremonies. Most commonly, institutions require candidates to wear the tassel on the right side and then shift it to the left side after receiving their degrees.
At the baccalaureate level and higher, the cap must be black to match the gown. Similarly, the tassel on the cap should match both the cap and gown. Candidates can wear tassels that are not black under two conditions. The academic costume code assigns colors to disciplines of study. Candidates can wear tassels colored to match their discipline. Doctorate holders can wear gold-colored tassels.
The length of the tassel remains constant regardless of degree level. Depending on the tradition of the particular institution, the position of the tassel changes according to degree level. Typically, baccalaureate candidates wear the tassel on the right side of the mortarboard until receiving their degrees. Master's candidates and holders wear the tassel to the left. Doctoral candidates and holders typically wear a velvet cap without points and the tassel lies however it falls.
Anyone involved in an academic procession who is a member of a religious order, the military or who holds a civil office that requires special attire is not bound by the customs of academic costume. Members of religious orders wear their customary habits and members of the military can choose to wear their dress uniform.