If the player character joins the Railroad and accepts the quest Tradecraft, Ricky can be convinced to cause a distraction (resulting in his death), or providing sniper support. He may still die with the sniper option, however, as he has been known to walk into landmines.
If asked to provide sniper support or a distraction, he may be flagged as dead, regardless of how one ultimately chooses to infiltrate the Switchboard, or when the synths in Slocum's Joe are killed and even if he survives, and this will count as a murder in the Pip-Boy's crime stats.
After the quest, he will rarely appear in the Sole Survivor's vicinity, including at Home Plate and within the city limits of Diamond City and Goodneighbor. Sometimes he will follow the player character, other times he will walk back and forth between two points. Interaction is normal, and upon exiting the cell he will disappear. It is unknown whether this is intended or not. However, if the player character were to make a save before he arrives, and reload the save after he leaves, he will appear again, at the same time. Because of this, it may be scripted.
Furthermore, if the player character chooses to betray the Railroad, Ricky may be hostile. Due to the low damage of his rifle this will likely be an annoyance more than a hindrance.
xboxonepcps4 If the player character is enemies with the Railroad, his essential flag may not be removed. If this is the case and he is hostile, he will chase the player relentlessly even after fast travel. You will only be able to get him in the wounded position and he will get right back up.You can NOT kill him. [verified]