Justice Sekhon, whose brother Janmeja Singh Sekhon is an Irrigation minister in the SAD-BJP government in Punjab, took oath as the new Lokpal on Friday.
His appointment drew instant protest from the state Congress which said he should have declined the offer for the sake of "moral and judicial propriety" as his brother was a minister in the Parkash Singh Badal government.
"There is every apprehension that it (the Lokpal) may overlook wrongdoings of the Akalis. On the other hand, it may falsely implicate opposition leaders particularly those of the Congress," Punjab Congress chief Amarinder Singh said.
Amarinder was talking to reporters in Nawanshahr district after attending a function on the death anniversary of former state Parliamentary Secretary Parkash Singh.
The Punjab government on November nine appointed Justice Sekhon, former Judge of Punjab and Haryana High Court, as Lokpal of the state.
In a letter to Punjab Governor Shivraj Patil this week, Amarinder had said "a state Lokpal is required to be an autonomous, unbiased and politically uncoloured individual mandated and empowered by the provisions of The Punjab Lokpal Act, 1996 to investigate and inquire into complaints of misconduct and corruption."