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Peter Laird is a civilian aeronautical engineer pressed into service by order of Admiral Helena Cain after the Cylon attack on the Twelve Colonies. He is aboard the civilian transport Scylla when it, along with several other vessels, is found by the battlestar Pegasus about a week after the attack. Admiral Cain places military priorities above all else and orders that the ships be scavenged for anything that would be of use to Pegasus: supplies, weapons, parts and skilled civilian personnel. Laird, because his aeronautics background, becomes a selectee for conscription into Pegasus's crew along with 14 other people on board.
Colonel Fisk and Lieutenant Shaw take a team of Marines to the Scylla to carry out the order. Laird speaks as the passengers' representative and refuses to cooperate. When Fisk's show of intimidation fails to persuade the civilians, Cain orders that the selectees' families be shot to demonstrate the alternative. Fisk continues his threat to shoot them, but Shaw takes the initiative and shoots one woman in the head, triggering the Marines to kill nine more. Word spreads throughout the civilian vessels and breaks all resistance, and Laird and the others are transfered to Pegasus. Laird's wife and family are likely among the dead, if not left behind (Razor).
He is put into uniform and assigned deck chief. When he pays Galactica a visit, he meets his counterpart, Chief Tyrol. Laird is both appalled and impressed by the Blackbird, Tyrol's new stealth fighter, and is surprised to find the plane is fitted with obsolete DDG-62 engines he designed (Pegasus).
Laird is transferred to Galactica as part of Admiral Cain's crew reassignments, and is made deck chief prior to Tyrol's arrest for Lt. Thorne's death . He also makes a suggestion to Galactica's deck crew that increases the Blackbird's fuel efficiency by two percent (Pegasus (Extended Version)).
Laird has difficulty managing the hangar deck as Tyrol's substitute and lacks military bearing, but assures Commander Adama that all ships will be ready for "the attack thing" (Resurrection Ship, Part I).
Following Admiral Cain's death, her crew transfers are reversed and Tyrol is re-instated as Galactica's deck chief. Laird presumably returns to his previous assignment as the Pegasus deck chief (Resurrection Ship, Part II).
Over two years later, Laird is promoted to Galactica's chief of the deck after Tyrol's demotion by Admiral Adama; he retrieves the navigational data from Eammon Pike's damaged Raptor that tells them where the rebel baseship jumped to (Sine Qua Non).
In the early stages of a mutiny aboard Galactica, Laird finds several individuals attempting to steal a Raptor reserved for emergency medical transport to fly Tom Zarek to Colonial One. Felix Gaeta attempts to convince Laird that this is simply a change of orders that he wasn't informed of, but when Laird moves to confirm that story, Zarek kills him by striking him in the head with a wrench (The Oath).