drivers stopped by traffic police in the U.S. suggests the possibility of biased policing against non-white drivers. Black drivers felt that they were being pulled over by law enforcement officers simply because of their skin color. However, some argue in favor of the "veil of darkness" hypothesis, which states that police are less likely to know the race of a driver before they make a stop at nighttime as opposed to in the daytime. Referring to the veil of darkness hypothesis, it is suggested that if the race distribution of drivers stopped during the day differs from that of drivers stopped at night, officers are engaging in racial profiling. For example, in one study done by Jeffrey Grogger and Greg Ridgeway, the veil of darkness hypothesis was used to determine whether or not racial profiling in traffic stops occurs in Oakland, California. The conductors found that there was little evidence of racial profiling in traffic stops made in Oakland. Research through random sampling in the South Tucson, Arizona area has established that immigration authorities sometimes target the residents of barrios with the use of possibly discriminatory policing based on racial profiling. Author Mary Romero writes that immigration raids are often carried out at places of gathering and cultural expression such as grocery stores based on the fluency of language of a person (e.g. being bilingual especially in Spanish) and skin color of a person. She goes on to state that immigration raids are often conducted with a disregard for due process, and that these raids lead people from these communities to distrust law enforcement. In a recent journal comparing the 1990s to the present, studies have established that when the community criticized police for targeting the black community during traffic stops it received more media coverage and toned down racial profiling. However, whenever there was a significant lack of media coverage or concern with racial profiling, the amount of arrests and traffic stops for the African-American community would significantly rise again. New York Police Department Suspicionless surveillance of Muslims Between 2003 and 2014, the New York City Police Department (NYPD) operated the "Demographics Unit" (later renamed "Zone Assessment Unit") which mapped communities of 28 "ancestries of interest", including those of Muslims, Arabs, and Albanians. Plain-clothed detectives were sent to public places such as coffee shops, mosques and parks to observe and record the public sentiment, as well as map locations