"Special projects" at Apple is believed to refer to the company's rumored Titan car project. The hire comes after Steve Zadesky, who is believed to have run the car project at Apple, left the company in January after a two year stint.
Porritt has had a long career in the automotive industry, having worked for Aston Martin as its chief engineer. It's not clear if Porritt has been hired to replace Zadesky on the Apple car project, or if he's simply joining the team to add expertise. Bloomberg reporter Dana Hull says Porritt left in September.
Apple and Tesla have been in a talent poaching war, and Tesla CEO Elon Musk has publicly had harsh words for Apple.
"They have hired people we've fired," Musk said in 2015. "We always jokingly call Apple the 'Tesla Graveyard.' If you don't make it at Tesla, you go work at Apple."
The Wall Street Journal reported in 2015 that Apple is planning to ship an all-electric vehicle by 2019. Apple is said to have made the Titan car project a "committed project" after looking at the feasibility of a car made by Apple.
Neither Apple nor Tesla have responded to request for comment on the hire.
Article updated with additional information about Porritt.