Kent appears before Lancaster, Mortimer Junior, Warwick, and Pembroke, saying that “love to this [their] native land” has compelled him to join forces with them. Lancaster and Warwick suspect that Edward has sent Kent as a spy, but Mortimer Junior trusts in Kent's honor, and the nobles accept him.
Although his allegiances shift over the course of the play, Kent is one of the few characters who does seem to follow his conscience first and foremost. His decision to join the rebel nobles, as he says, stems from a sense of loyalty to England that outweighs his personal loyalty to his brother.
Lancaster explains that Gaveston and Edward are “frolicking” in Tynemouth, and the nobles resolve to attack the castle, with Mortimer Junior declaring that he will raise the “tattered ensign of [his] ancestors.” Although Lancaster warns the group against laying hands on the King, he urges them to kill Gaveston and his friends.
Despite the fact that the nobles are at this point planning to attack the castle where Edward currently resides, they are still at least paying lip service to their allegiance to the King. As of now, their plan is to avoid deposing or even harming Edward if possible. This again suggests that Edward continues to command a certain amount of respect simply by virtue of being king, regardless of the nobility's many complaints with his style of ruling.