It's unclear if they have a certain personality that makes them more resistant or if the situation was different they would also give in to the group or authority figure
People with an internal locus of control are more likely to resist authority figures as they feel better equipped to stand against them and have a drive to refuse orders that don't match their values
Holland's replication of Milgram showing 37% of internals refused to continue compared to 23% of externals
Specter's research showing a correlation between external locus of control and resistance to normative social influence but not informational social influence
The relationship between locus of control and resistance to social influence is correlational, and there are other factors that could also influence resistance such as social anxiety, personal morality, and social status