Idk what objective you achieve in such skewed analysis but let's get the ground picture.

Population of Karachi : 15 million (2017) Population of Delhi : 18 million (2017) Number of murders in Karachi in 2017 : 606 Number of murders in Delhi in 2017 : 487 Number of murders per 100k people in Karachi : 4.02 Number of murders per 100k people in Delhi : 2.70 Since Safety is considered for all the people residing in the city. No Matter how you look at it Delhi is still safer to live in than Karachi.

In the same time 202,025 criminals were arrested. Some 3,560 murderers arrested, 1,987 terrorists, 186 kidnappers, 836 extortionists, 7,401 dacoits, 33,026 arrested keeping illegal weapon, 32,048 arrested in narcotics ordinance, 94,458 arrested in petty crimes. 2,434 proclaimed offenders arrested and 26,095 absconders arrested.

In the meantime some 41,917 illegal arms were recovered, including 73 Light Machine Guns (LMGs), 906 Kalashnikovs, 39,519 pistols, 826 rifles, 593 short guns repeaters; 619 explosive material, 9 Improvised Explosive Devices (IEDs), 23 suicide jackets, 807 bombs (hand grenades) were seized.

Karachi has indeed come a long way, but it still has a long way to go. Also the fact that the situation got so bad that army had to intervene into the previously terrorist infestated city doesn't help either.

Their are not enough cops to safeguard the population either. (Lesser than Delhi)

It is pertinent to mention here that London, a city of 7,387,868 (half that of Karachi) relatively law-abiding citizens has a police strength of 47,874, a ratio of 1,155. Delhi with a population of 14,000,000 has a police force of 58,000, a ratio of 1,241. Lahore with its 10,000,000 has a force of 30,946, a ratio of 1323 and Karachi with estimated population 18,000,000 have a force of 34,212, a ratio of 1,526.