The court said on Friday that it had finished interrogating all 18 witnesses and would make its ruling at 1.30pm on Wednesday.
The witnesses included Pol Maj Gen Kajornsak Pansakorn, deputy chief of the Metropolitan Police Bureau; Yutthana Phraedam, a special case official with the Department of Special Investigation (DSI), and 16 other officers who were stationed at polling stations for advance voting last Sunday.
The DSI is making its second try to obtain court approval to move against protest leaders on charges of obstructing the election process and violating the emergency decree.
Those sought by officers are members of the People's Democratic Reform Committee, the Dhamma Army, the People's Democratic Force to Overthrow Thaksinism and the Network of Students and People for the Reform of Thailand.
They are Suthep Thaugsuban, Sathit Wongnongtoey, Chumpol Julsai, Phutthipong Punnakan, Issara Somchai, Witthaya Kaewparadai, Thaworn Senneam, Nataphol Teepsuwan, Akanat Promphan, Anchalee Paireerak, Nitithorn Lamlua, Uthai Yodmanee, Samdin Lertbutr, Gen Preecha Iamsuphan, Ratchayut Sirayothinpakdi, Kittichai Saisa-ard, Samran Rodpech, Sonthiyan Chuenruethainaitham and Pansuwan Nakaew.
The request was filed by Pol Maj Gen Yutthana.
The court on Tuesday rejected the DSI's first petition to obtain arrest warrants for the 16 leaders as there was not enough evidence to substantiate the applications. The DSI added another three people to its list later.