legtools.remove's input validation does not check the values of the removal indices to see if they are valid indices. In the case of multiple deletion indices this error is handled by MATLAB, which throws an error when attempting to delete something out of range. However, in the case of one removal index, remove is short-circuited to remove the legend entirely if there is also only one legend entry.

For example:

figure ezplot sin legend sin legtools.remove(legend,2) 

See also: #7