Lisa Murkowski, a longtime senator from Alaska and an independent voice in an increasingly tribal party, has been the rare Republican on Capitol Hill willing to criticize President Trump’s actions.

Moderate Alaska GOP Sen. Lisa Murkowski claimed this week that she and other lawmakers are worried about retaliation for speaking out against some of the Trump administration’s policies.

Sen. Lisa Murkowski said a fear of retaliation under President Donald Trump’s administration is rising to levels she’s not seen before, acknowledging this week that it is so pervasive that ...