Lewis was embroiled in a war of words with the Spaniard during the UK Open qualifier quarter-final before appearing to push Justicia in the chest after winning the match 6-5.
After security intervened, the incident was referred to the Darts Regulation Authority for immediate consideration and Lewis - who lost in the semi-finals to Michael van Gerwen - was later suspended pending a full investigation.
Lewis has admitted a breach of DRA rules and been handed a suspended ban and a £3,000 fine.
The PDC said in a statement on Thursday morning: "On Wednesday, February 7, the DRA disciplinary committee heard the case of Adrian Lewis concerning the incidents in his match with Jose Perales on Friday, February 2, 2018.
"Mr Lewis has been suspended since the incident. He admitted breaching the DRA rules and received a three-month suspension from competing which is suspended for six months. He was also fined £3,000."
Lewis, 33, has experienced a tough couple of months after suffering a first-round exit at the World Championship and losing his place in the Premier League, and he also released a statement expressing his regret at the incident.
He said: "I deeply regret that my frustrations got the better of me as I felt my opponent was trying to provoke me.
"I realise now that I should have reported any problems to tournament officials instead of confronting Jose Antonio Justicia Perales after the match.
"I would like to offer my sincere apologies to the PDC, the sponsors of the event Coral, my own sponsors, who I thank for their loyalty and support, my manager, darts fans and finally my family.
"I would like to say a big thank you for all of the kind messages sent to me from all over the world, and now I just want to put all this behind me and concentrate on playing the game I love and trying to make my way back to the top."
Hear what Sporting Life darts expert Chris Hammer and pundit John Part made of the incident by listening to our darts podcast, available to download now via iTunes
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