Former defence minister Hishammuddin Hussein has slammed the government for what he described as a "fishing expedition" to compel opposition lawmakers to declare their assets.

He said this was because the government had failed to lead by example, with MPs from the ruling coalition yet to declare their assets.

"There are 12 MPs who have yet to declare their assets and 22 have not declared the assets of their families, including one senator who is also a deputy minister," Hishammuddin told the media at the Parliament building's lobby today.

"So, asking the opposition to do something is like a fishing expedition to me. You have to lead by example.

"Prove to us that you are sincere. Prove to us that what you are trying to do is transparent for the sake of the public because you are in power," the Sembrong MP added.

Hishammuddin was asked if he or other opposition MPs would declare their assets.

Yesterday, the Dewan Rakyat passed a motion to compel all lawmakers to declare their assets within three months.

Failing to do so, they would be referred to the Parliamentary Rights and Privileges Committee.

Elaborating, Hishammuddin said the asset declaration exercise of MPs made no sense to him as they had declared their assets with the Inland Revenue Board.

On another development, Hishammuddin doubted 18-year-olds, under the strong influence of social media, have the maturity to vote for the right party.

As such, he urged the government to conduct an in-depth study before tabling a bill to lower the voting age to 18 in the current Dewan Rakyat sitting.

"The government needs to ensure the youth voters get sufficient valid information.

“I am not saying that they are not responsible, but there are new tools now that can influence (them) emotionally.

“If the repercussions to reduce the voting age backfire, then it’s too late for us. I hope whoever is proposing it conducts a thorough study,” he said.