Federation Commander

According to the rules degraded marines suffer a +1 but if the attacker, who is degraded, boards the ship to take it over then the +1 helps them to kill more marines. Should the +1 apply to both raids and in capture attempts or is there another rule for trying to capture a ship while degraded.

The rule says: "... and during hand-to-hand combat (5F2b) the enemy Marines get a +1 to their die roll." (Bold added here.)

It is the enemy's marines that get the bonus, not the degraded crew marines. So, yes, the +1 causes more damage to be done, but it is happening against the degraded crew, not for it.

Thanks MJWEST. That makes sense.