Answered by Shaykh Faraz Rabbani
How is it to do imamat and pray Namaz in Pants?
[From external source, unedited: (Fatwa from Monthly Kanzuliman-India)http://www.islamicacademy.org/html/Fatwa/English/Namaaz_in_Pants.htm
A: In the past only British used to wear pants. One who wore pants used to be considered a British. But now Muslims, Hindus and other nations wear pants excessively. Therefore now the pants are not a dress of any particular nation. If a dress, which is not particular to a nation or used to be particular to a nation but it’s now a common dress will not be called a specific dress of any nation. Even though that dress was invented by a nation. Syedna Ala hazrat Imam Ahmad Raza Muhaddise Barelvi Aleh Rehmat-o-Riawan writes in Fatawa-e-Rizvia in Part 9 on page 91 that “Only that resemblance is prohibited or Makrooh in which a person’s intention is to resemble or that thing is a way of Bud Mazhab or holds some kind of state against Shariat.
In the absence of these mentioned conditions definitely there is no reason for prohibition” In the same book it is mentioned under Mawahibe Ludnyah Hazrat Allama Qastalani Rehamatullah Aleh says about the dress of Jews,*1. Therefore if the pants are loose enough that it will not be cumbersome to perform Namaaz, it is allowed to perform Namaaz wearing them. But they should not be so long that they will cover the bones of ankles otherwise Namaaz will be Makrooh. If it’s because of pride it is Makrooh-e-Threemi otherwise Makrooh-e-Tanzeehi. Strict Muslims in our area still dislike wearing pants and consider them improper. Therefore for such an important post of imamat wearing pants is not proper. Syedna Alahazrat Imam Ahmad Raza Muhaddise Barelvi Aleh Rehmat-o-Riawan writes,*2 (Fatawa-e-Rizvia, part 9 page 38) Allah Tala knows the best.