Liberalism is for protection of civil liberties such as free speech. Tyler Robinson wasn't exhibiting liberal ideology when he shot Kirk for what he deemed as hate speech.
civil liberty
pluralcivil liberties
: freedom from arbitrary interference in one's speech or actions by other individuals or by the government especially as constitutionally guaranteed (as by the U.S.
Bill of Rights)
—usually plural
Examples of civil liberties include freedom of speech, freedom of religion, freedom of assembly, freedom of the press, the right to privacy, and the right to due process of law.—Ramon Martin
compare
civil rights
liberalism
lib·er·al·ism
ˈli-b(ə-)rə-ˌli-zəm
pluralliberalisms
Synonyms of liberalism
1
: inclination to be open to ideas and ways of behaving that are not conventional or traditional
Raised by parents who prided themselves on their liberalism and charity, she was encouraged to romp with her brothers, to succeed in her schooling and to absorb her father's patriotic war stories.—Susan Reverby
compare
conservatism sense 1a
2
a
see usage paragraph below
: a political philosophy based on belief in progress and stressing the essential goodness of the human race,
freedom for the individual from arbitrary authority, and protection and promotion of political and civil liberties