MANILA - A lawyer who uses the Angkas motorcycle service has filed a case in a Mandaluyong court challenging the constitutionality of the city's ordinance regulating "riding-in-tandem" motorcyclists.

Lawyer Dino de Leon filed the case on after getting apprehended near a mall in the Ortigas Center while riding the Angkas motorcycle ride-hailing service last March 7.

Mandaluyong bans males from backriding on motorcycles, unless they are immediate family members or law enforcers.

The city has said that the measure is meant to reduce the number of crimes committed by riding-in-tandem motorcyclists.

But de Leon contends that the ordinance is unconstitutional because it discriminates against males, thus violating the equal protection clause of the Constitution.

Under the equal protection clause, if people are similarly situated, they should be legally treated equally, de Leon said in an interview with ABS-CBN News.

"So hindi porke lalake or babae eh may ibang treatment na unless there's a valid reason to classify," he said.

He added that the ordinance has no valid reason to discriminate against male backriders because there is no empirical basis in terms of its effectiveness.

"I could have just paid the fine and move on, but when will such small abuses end? As a citizen, I deemed it right to use legal forums to at least discuss the constitutionality of the ordinance, and in effect, also its policy basis," de Leon said in a statement posted on his Facebook page.

He added that various motorcycle groups have offered to help him in his case.

The Motorcycle Rights Organization said in a Facebook post that it was willing to assist in de Leon's petition.